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Adaptive Spindle Balancing Using Magnetically Levitated Bearings (open access)

Adaptive Spindle Balancing Using Magnetically Levitated Bearings

A technological break through for supporting rotating shafts is the active magnetic bearing (AMB). Active magnetic bearings offer some important advantages over conventional ball, roller or journal bearings such as reduced frictional drag, no physical contact in the bearing, no need for lubricants, compatibility with high vacuum and ultra-clean environments, and ability to control shaft position within the bearing. The disadvantages of the AMB system are the increased cost and complexity, reduced bearing stiffness and the need for a controller. Still, there are certain applications, such as high speed machining, biomedical devices, and gyroscopes, where the additional cost of an AMB system can be justified. The inherent actuator capabilities of the AMB offer the potential for active balancing of spindles and micro-shaping capabilities for machine tools, The work presented in this paper concentrates on an AMB test program that utilizes the actuator capability to dynamically balance a spindle. In this study, an unbalanced AMB spindle system was enhanced with an LMS (Least Mean Squares) algorithm combined with an existing PID (proportional, integral, differential) control. This enhanced controller significantly improved the concentricity of an intentionally unbalanced shaft. The study included dynamic system analysis, test validation, control design and simulation, as well …
Date: September 20, 1999
Creator: BARNEY,PATRICK S.; LAUFFER,JAMES P.; PETTEYS,REBECCA; REDMOND,JAMES M. & SULLIVAN,WILLIAM N.
Object Type: Article
System: The UNT Digital Library
Airline Deregulation: Changes in Airfares and Service at Buffalo, New York (open access)

Airline Deregulation: Changes in Airfares and Service at Buffalo, New York

Testimony issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO discussed changes in airfares and service quality at Buffalo Niagara International Airport since deregulation."
Date: September 20, 1999
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Alternative Evaluation for the REDOX (202-S) Plutonium Loadout Hood (open access)

Alternative Evaluation for the REDOX (202-S) Plutonium Loadout Hood

Located in the 200 Areas is the inactive 202-S Reduction Oxidation (REDOX) Facility, which is managed by the Bechtel Hanford, Inc. Surveillance/Maintenance and Transition project. This facility is contaminated from nuclear material processes related to nuclear material separation from Hanford Site facility operations. This alternative evaluation report describes the alternatives and selection criteria based on the necessary protective requirements to maintain the REDOX Plutonium Loadout Hood in a safe and stable condition awaiting a final waste response action.
Date: September 20, 1999
Creator: Kerr, N. R.
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 100, No. 156, Ed. 1 Monday, September 20, 1999 (open access)

Altus Times (Altus, Okla.), Vol. 100, No. 156, Ed. 1 Monday, September 20, 1999

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: September 20, 1999
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 108, No. 114, Ed. 1 Monday, September 20, 1999 (open access)

The Alvin Sun (Alvin, Tex.), Vol. 108, No. 114, Ed. 1 Monday, September 20, 1999

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: September 20, 1999
Creator: Schwind, Jim & Holton, Kathleen
Object Type: Newspaper
System: The Portal to Texas History
An Analysis of the HEW-MET-FAST-035 Problem Using CENTRM and SCALE (open access)

An Analysis of the HEW-MET-FAST-035 Problem Using CENTRM and SCALE

An U/Fe benchmark, designated as HEU-MET-FAST-035, has been approved for inclusion in the International Handbook of Evaluated Criticality Safety Benchmark Experiments. The SCALE code and cross sections performed poorly in calculating this critical experiment. Deficiencies in both the ENDF/B-V representation of the resonance region for Fe and in the Nordheim integral treatment when applied to Fe were identified. The combination of these deficiencies led to an almost 10% over-prediction of k(eff). Problems involving a large percentage of Fe and intermediate-energy spectrums present special cross-section processing difficulties for SCALE. In ENDF/B-V, resonance data for Fe only go to 400 keV, although resonances are present well above 1 MeV. Significant resonance data are stored as file 3 data instead of as resonance parameters. The Nordheim Integral Treatment used in NITAWL to process cross sections assume: resonances are widely spaced and all relevant information is contained in the resonance parameters (file 3 data is not processed). These limitations and assumptions result in poor solutions for this class of problems.
Date: September 20, 1999
Creator: Hollenbach, D. F. & Jordan, W. C.
Object Type: Article
System: The UNT Digital Library
Analytical Benchmark Test Set for Criticality Code Verification (open access)

Analytical Benchmark Test Set for Criticality Code Verification

A number of published numerical solutions to analytic eigenvalue (k{sub eff}) and eigenfunction equations are summarized for the purpose of creating a criticality verification benchmark test set. The 75-problem test set allows the user to verify the correctness of a criticality code for infinite medium and simple geometries in one- and two-energy groups, one- and two-media, and both isotropic and linearly anisotropic neutron scattering. A three- and six-energy group infinite medium problem are also included in the test set. The problem specifications will produce both k{sub eff}=1 and the quoted k{sub {infinity}} to at least five decimal places. Additional uses of the test set for code verification are also discussed. Los Alamos report LA-13511 contains the details of all 75 test problems.
Date: September 20, 1999
Creator: Sood, A.; Forster, R. A. & Parson, D. K.
Object Type: Article
System: The UNT Digital Library
Application of Telepresence Technologies to Nuclear Material Safeguards (open access)

Application of Telepresence Technologies to Nuclear Material Safeguards

Implementation of remote monitoring systems has become a priority area for the International Atomic Energy Agency and other international inspection regimes. For the past three years, DOE2000 has been the US Department of Energy's (DOE's) initiative to develop innovative applications to exploit the capabilities of broadband networks and media integration. The aim is to enhance scientific collaboration by merging computing and communications technologies. These Internet-based telepresence technologies could be easily extended to provide remote monitoring and control for confidence building and transparency systems at nuclear facilities around the world. One of the original DOE2000 projects, the Materials Microcharacterization Collaboratory is an interactive virtual laboratory, linking seven DOE user facilities located across the US. At these facilities, external collaborators have access to scientists, data, and instrumentation, all of which are available to varying degrees using the Internet. Remote operation of the instruments varies between passive (observational) to active (direct control), in many cases requiring no software at the remote site beyond a Web browser. Live video streams are continuously available on the Web so that participants can see what is happening at a particular location. An X.509 certificate system provides strong authentication, The hardware and software are commercially available and are …
Date: September 20, 1999
Creator: Wright, M.C. & Rome, J.A.
Object Type: Article
System: The UNT Digital Library
APT Blanket Thermal Analyses of Top Horizontal Row 1 Modules (open access)

APT Blanket Thermal Analyses of Top Horizontal Row 1 Modules

The Accelerator Production of Tritium (APT) cavity flood system (CFS) is designed to be the primary safeguard for the integrity of the blanket modules during loss of coolant accidents (LOCAs). For certain large break LOCAs the CFS also provides backup for the residual heat removal systems (RHRs) in cooling the target assemblies. In the unlikely event that the internal flow passages in a blanket module or target assembly dryout, decay heat in the metal structures will be dissipated to the CFS through the module or assembly walls (i.e., rung outer walls). The target assemblies consist of tungsten targets encased in steel conduits, and they can safely sustain high metal temperatures. Under internally dry conditions, the cavity flood fluid will cool the target assemblies with vigorous nucleate boiling on the external surfaces. However, the metal structures in the blanket modules consist of lead cladded in aluminum, and they have a long-term exposure temperature limit currently set to 150 degrees C. Simultaneous LOCAs in both the target and blanket heat removal systems (HRS) could result in dryout of the target ladders, as well as the horizontal blanket modules above the target. The cavity flood coolant would boil on the outside surfaces of …
Date: September 20, 1999
Creator: Shadday, M.A.
Object Type: Report
System: The UNT Digital Library
BAR-CODE BASED WEIGHT MEASUREMENT STATION FOR PHYSICAL INVENTORY TAKING OF PLUTONIUM OXIDE CONTAINERS AT THE MINING AND CHEMICAL COMBINE RADIOCHEMICAL REPROCESSING PLANT NEAR KRASNOYARSK, SIBERIA. (open access)

BAR-CODE BASED WEIGHT MEASUREMENT STATION FOR PHYSICAL INVENTORY TAKING OF PLUTONIUM OXIDE CONTAINERS AT THE MINING AND CHEMICAL COMBINE RADIOCHEMICAL REPROCESSING PLANT NEAR KRASNOYARSK, SIBERIA.

This paper describes the technical tasks being implemented to computerize the physical inventory taking (PIT) at the Mining and Chemical Combine (Gorno-Khimichesky Kombinat, GKhK) radiochemical plant under the US/Russian cooperative nuclear material protection, control, and accounting (MPC and A) program. Under the MPC and A program, Lab-to-Lab task agreements with GKhK were negotiated that involved computerized equipment for item verification and confirmatory measurement of the Pu containers. Tasks under Phase I cover the work for demonstrating the plan and procedures for carrying out the comparison of the Pu container identification on the container with the computerized inventory records. In addition to the records validation, the verification procedures include the application of bar codes and bar coded TIDs to the Pu containers. Phase II involves the verification of the Pu content. A plan and procedures are being written for carrying out confirmatory measurements on the Pu containers.
Date: September 20, 1999
Creator: Suda, S.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 77, No. 278, Ed. 1 Monday, September 20, 1999 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 77, No. 278, Ed. 1 Monday, September 20, 1999

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: September 20, 1999
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+delta} c-axis twist Josephson junctions : a new phase-sensitive test of order parameter symmetry. (open access)

Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+delta} c-axis twist Josephson junctions : a new phase-sensitive test of order parameter symmetry.

Li et al. found that the critical current density J{sub c}{sup J} across atomically clean c-axis twist junctions of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} is the same as that of the constituent single crystal, J{sub c}{sup S}, independent of the twist angle {phi}{sub 0}, even at and below T{sub c}. They investigated theoretically if a d{sub x{sup 2}{minus}y{sup 2}} wave order parameter might twist by mixing in d{sub xy}-wave components, but found that such mixing cannot possibly explain the data near to T{sub c}. Combined with group theoretical arguments, they then conclude that the order parameter contains at least a substantial s-wave component, but does not contain any purported d{sub x{sup 2}{minus}y{sup 2}}-wave component, except possibly below a second, unobserved phase transition. By studying tunneling models, they further conclude that the intrinsic c-axis Josephson tunneling in Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} is likely to be mostly incoherent.
Date: September 20, 1999
Creator: Klemm, R. A.; Arnold, G.; Bille, A.; Rieck, C. T. & Scharnberg, K.
Object Type: Article
System: The UNT Digital Library
Bipolaron Hopping Conduction in Boron Carbides (open access)

Bipolaron Hopping Conduction in Boron Carbides

The electrical conductivities of boron carbides, B{sub 12+x}C{sub 3{minus}x} with 0.1 < x < 1.7, between 300 and 1200K suggest the hopping of a nearly temperature-independent density of small (bi)polarons. The activation energies of the nobilities are low, {approx} 0.16 eV, and are nearly independent of the composition. At lower temperatures, conductivities have non-Arrhenius temperature dependencies and strong sensitivity to carbon concentration. Percolative aspects of low-temperature hopping are evident in this sensitivity to composition. Boron carbides' Seebeck coefficients are anomalous in that (1) they are much larger than expected from boron carbides' large carrier densities and (2) they depend only weakly on the carrier density. Carrier-induced softening of local vibrations gives contributions to the Seebeck coefficient that mirror the magnitudes and temperature dependencies found in boron carbides.
Date: September 20, 1999
Creator: ASELAGE, TERRENCE L.; EMIN, D. & MCCREADY, STEVEN S.
Object Type: Article
System: The UNT Digital Library
Blood Supply: Availability of Blood to Meet the Nation's Requirements (open access)

Blood Supply: Availability of Blood to Meet the Nation's Requirements

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on the availability of blood to meet the nation's requirements, focusing on: (1) recent trends in blood donation and the demand for blood transfusions; (2) the expected effect of a ban on blood from donors who have travelled to the United Kingdom; and (3) the potential effect of policy changes to allow units of blood collected from individuals with hemochromatosis to be distributed."
Date: September 20, 1999
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Bounding Values for Low-Level-Waste Transport Exemptions and Disposal (open access)

Bounding Values for Low-Level-Waste Transport Exemptions and Disposal

Characterizations and bounding computational results determined by the Oak Ridge National Laboratory have been offered to the U.S. Nuclear Regulatory Commission as supporting technical bases for regulatory considerations in the packaging, transport, retrievable emplacement and disposal of radioactive low-level waste contaminated with fissile materials. The fissile materials included 100 wt % U, 10 wt % U in uranium, 100 wt % U, 100 wt % Pu, or plutonium as less than 235 235 233 239 76 wt % Pu, more than 12 wt % Pu, and less than 12 wt % Pu. The considered waste matrixes 239 240 241 included silicon dioxide, carbon, light water and polyethylene, heavy water, or beryllium with summary examinations of other potential matrixes. The limiting concentrations and geometries for these bounding conjectured low-level-waste matrixes are presented in this paper.
Date: September 20, 1999
Creator: Hopper, Calvin M.; Elam, Karla R.; Parks, Cecil V. & Lichtenwalter, Jerry J.
Object Type: Article
System: The UNT Digital Library
CHARACTERIZATION OF THE COHERENT NOISE, ELECTROMAGNETIC COMPATIBILITY AND ELECTROMAGNETIC INTERFERENCE OF THE ATLAS EM CALORIMETER FRONT END BOARD (open access)

CHARACTERIZATION OF THE COHERENT NOISE, ELECTROMAGNETIC COMPATIBILITY AND ELECTROMAGNETIC INTERFERENCE OF THE ATLAS EM CALORIMETER FRONT END BOARD

The ATLAS Electromagnetic (EM) calorimeter (EMCAL) Front End Board (FEB) will be located in custom-designed enclosures solidly connected to the feedtroughs. It is a complex mixed signal board which includes the preamplifier, shaper, switched capacitor array analog memory unit (SCA), analog to digital conversion, serialization of the data and related control logic. It will be described in detail elsewhere in these proceedings. The electromagnetic interference (either pick-up from the on board digital activity, from power supply ripple or from external sources) which affects coherently large groups of channels (coherent noise) is of particular concern in calorimetry and it has been studied in detail.
Date: September 20, 1999
Creator: CHASE,B. CITTERIO,M. LANNI,F. MAKOWIECKI,D. RADEKA,S. RESCIA,S. TAKAI,H. ET AL.
Object Type: Article
System: The UNT Digital Library
Computational Methods for Sensitivity and Uncertainty Analysis in Criticality Safety (open access)

Computational Methods for Sensitivity and Uncertainty Analysis in Criticality Safety

Interest in the sensitivity methods that were developed and widely used in the 1970s (the FORSS methodology at ORNL among others) has increased recently as a result of potential use in the area of criticality safety data validation procedures to define computational bias, uncertainties and area(s) of applicability. Functional forms of the resulting sensitivity coefficients can be used as formal parameters in the determination of applicability of benchmark experiments to their corresponding industrial application areas. In order for these techniques to be generally useful to the criticality safety practitioner, the procedures governing their use had to be updated and simplified. This paper will describe the resulting sensitivity analysis tools that have been generated for potential use by the criticality safety community.
Date: September 20, 1999
Creator: Broadhead, B. L.; Childs, R. L. & Rearden, B. T.
Object Type: Article
System: The UNT Digital Library
Conduit Fasteners (open access)

Conduit Fasteners

W-441, Cold Vacuum Drying Facility (CVD), CGI, Conduit Fasteners.
Date: September 20, 1999
Creator: Van Katwijk, Carl
Object Type: Report
System: The UNT Digital Library
The Criticality Safety Information Resource Center (CSIRC) at Los Alamos National Laboratory (open access)

The Criticality Safety Information Resource Center (CSIRC) at Los Alamos National Laboratory

The Criticality Safety Information Resource Center (CSIRC) at Los Alamos National Laboratory (LANL) is a program jointly funded by the U.S. Department of Energy (DOE) and the U.S. Nuclear Regulatory Commission (NRC) in conjunction with the Defense Nuclear Facilities Safety Board (DNFSB) Recommendation 97-2. The goal of CSIRC is to preserve primary criticality safety documentation from U.S. critical experimental sites and to make this information available for the benefit of the technical community. Progress in archiving criticality safety primary documents at the LANL archives as well as efforts to make this information available to researchers are discussed. The CSIRC project has a natural linkage to the International Criticality Safety Benchmark Evaluation Project (ICSBEP). This paper raises the possibility that the CSIRC project will evolve in a fashion similar to the ICSBEP. Exploring the implications of linking the CSIRC to the international criticality safety community is the motivation for this paper.
Date: September 20, 1999
Creator: Henderson, Barbara D.; Meade, Roger A. & Pruvost, Norman L.
Object Type: Article
System: The UNT Digital Library
Data Collection Guidelines for Consistent Evaluation of Data from Verification and Monitoring Safeguard Systems (open access)

Data Collection Guidelines for Consistent Evaluation of Data from Verification and Monitoring Safeguard Systems

One of the several activities the International Atomic Energy Agency (IAEA) inspectors perform in the verification process of Safeguard operations is the review and correlation of data from different sources. This process is often complex due to the different forms in which the data is presented. This paper describes some of the elements that are necessary to create a ''standardized'' structure for the verification of data. When properly collected and formatted, data can be analyzed with off-the shelf software applications using customized macros to automate the commands for the desired analysis. The standardized-data collection methodology is based on instrumentation guidelines as well as data structure elements, such as verifiable timing of data entry, automated data logging, identification codes, and others. The identification codes are used to associate data items with their sources and to correlate them with items from other data logging activities. The addition of predefined parameter ranges allows automated evaluation with the capability to provide a data summary, a cross-index of all data related to a specific event. Instances of actual databases are used as examples. The data collection guidelines described in this paper facilitate the use of data from a variety of instrumentation platforms and also allow …
Date: September 20, 1999
Creator: Castleberry, K.; Lenarduzzi, R. & Whitaker, M.
Object Type: Article
System: The UNT Digital Library
Development and Testing of a Jet Assisted Polycrystalline Diamond Drilling Bit. Phase II Development Efforts (open access)

Development and Testing of a Jet Assisted Polycrystalline Diamond Drilling Bit. Phase II Development Efforts

Phase II efforts to develop a jet-assisted rotary-percussion drill bit are discussed. Key developments under this contract include: (1) a design for a more robust polycrystalline diamond drag cutter; (2) a new drilling mechanism which improves penetration and life of cutters; and (3) a means of creating a high-pressure mud jet inside of a percussion drill bit. Field tests of the new drill bit and the new robust cutter are forthcoming.
Date: September 20, 1999
Creator: Pixton, David S.
Object Type: Report
System: The UNT Digital Library
Edge State Propagation Direction in the Fractional Quantum Hall Regime: Multi-Terminal Magnetocapacitance Experiment (open access)

Edge State Propagation Direction in the Fractional Quantum Hall Regime: Multi-Terminal Magnetocapacitance Experiment

The propagation direction of fractional quantum Hall effect (FQHE) edge states has been investigated experimentally via the symmetry properties of the multi-terminal capacitances of a two dimensional electron gas. Although strong asymmetries with respect to zero magnetic field appear, no asymmetries with respect to even denominator Landau level filling factor {nu} are seen. This indicates that current-carrying FQHE edge states propagate in the same direction as integer QHE edge states. In addition, anomalous capacitance features, indicative of enhanced bulk conduction, are observed at {nu} = 1/2 and 3/2.
Date: September 20, 1999
Creator: Johnson, B. L.; Moon, Jeong-Sun; Reno, John L. & Simmons, Jerry A.
Object Type: Article
System: The UNT Digital Library
Emissions Characterization in the Contained Underground Demilitarization Laboratory at Nevada Test Site (open access)

Emissions Characterization in the Contained Underground Demilitarization Laboratory at Nevada Test Site

The US Departments of Defense and Energy (DOD and DOE) have established a Joint Demilitarization Technology (JDT) Program to demonstrate and validate technologies for resource recovery and recycling, as well as alternative destruction or treatment technologies as appropriate to specific conventional stockpile segments. X-Tunnel at the DOE Nevada Test Site is a facility for emissions characterization from detonation of conventional munitions and burning of rocket motors. We conducted seven detonations of M107, high explosive 155-mm projectiles, four from December 1996 through March 1997 and three during July and August 1999. We also completed three burns of rocket motors from May through June 1997.Standard (DOD) procedures for open detonation (DOD) of ordinance and open burn (OB) of rocket motors were followed in order to establish baseline emissions. Measurements inside the chamber included pressures, temperatures, relative humidity and gas concentrations. Grab samples were collected f or gas, organic, metal and particulate analyses. Results and implications for developing alternative destruction techniques will be presented.
Date: September 20, 1999
Creator: Velsko, C. A.; Watkins, B. E.; Pruneda, C. O. & Lipkin, J
Object Type: Article
System: The UNT Digital Library
The Exchange Stabilization Fund of the U.S. Treasury Department: Purpose, History, and Legislative Activity (open access)

The Exchange Stabilization Fund of the U.S. Treasury Department: Purpose, History, and Legislative Activity

None
Date: September 20, 1999
Creator: Wilson, Arlene
Object Type: Report
System: The UNT Digital Library