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A 3-D ray-trace model for an AMR code on distributed processors

Description: Distributed memory AMR codes provide a special challenge for laser ray-trace modeling. For RAGE we follow the energy-carrying rays through each cell, checking for crossings which require collection a new cell index (1 of 9 in 2D). Density gradients for ray deflections can be calculated 'on the fly.' Substantial excursions must be made from the legacy PIC particle area-weighting approach, but this serves as a useful 1st step. Similarly, IDL now offers a quick graphical rendering, while ENSIGHT graphics beautifully captures the 3D light refraction and deposition.
Date: January 1, 2002
Creator: Mason, R. J. (Rodney J.)
Partner: UNT Libraries Government Documents Department
open access

25 years of technical advances in RFQ accelerators

Description: The radio frequency quadrupole (RFQ) accelerator began as 'The ion linear accelerator with space-uniform strong focusing' conceived by I. M. Kapchinskii and V. A. Teplyakove. In 1979, R. H. Stokes, K. R. Crandall, J. E. Stovall and D. A. Swenson gave this concept the name RFQ. And by 1983, at least 15 laboratories throughout the world were working on various FWQ designs. In the early years, there were many types of geometry considered for the RFQ, but only a few types have survived. The two cavity geometries now used in almost all RFQs are the 4-vane and 4-rod structures. The 4-vane structure is the most popular because its operating frequency range (80 to -500 MHz) is suitable for light ions. Heavy ions require low frequencies (below 200 MHz). Because the 4-rod structure has smaller transverse dimensions than a 4-vane RFQ at the same frequency, the 4-rod RFQ is often preferred for these applications. This paper will describe how the RFQ accelerates and focuses the beam. The paper also discusses some of the important technical advances in designing and building RFQs.
Date: January 1, 2002
Creator: Young, L. M. (Lloyd M.)
Partner: UNT Libraries Government Documents Department
open access

148-Gd cross section measurements for accelerator target facilities

Description: In a series of experiments at LANSCE's WNR facility, 148Gdp roduction was measured for 600- and 800-MeV protons on tungsten, tantalum, and gold. These experiments used 3 pm thin W, Ta, and Au foils and 10 pm thin A1 activation foils, Spallation yields were determined for many short-lived and long-lived spallation products with these foils using gamma and alpha spectroscopy.
Date: January 1, 2002
Creator: Corzine, R. K. (R. Karen); Pitcher, E. J. (Eric J.); Devlin, M. J. (Matthew J.) & Hertel, N. E. (Nolan E.)
Partner: UNT Libraries Government Documents Department
open access

360 Degree Photography to Decrease Exposure, Increase Safety & Minimize Waste

Description: High-resolution digital cameras, in conjunction with software techniques. make possible 360{sup o} photos that allow a person to look all around, up and dawn, and zoom in or out. The software provides the opportunity to attach other information to a 360{sup o} photo such as sound tiles, flat photos (providing additional detail about what is behind a panel or around a corner) and text (Information which can be used to show radiological conditions or identify other hazards not readily visible). The software also allows other 360{sup o} photos to be attached creating a virtual tour where the user can move from area to area, and stop, study and zoom in on areas of interest. A virtual tour of a building or room can be used for facility documentation, informing management and others, work planning and orientation, and training, thus minimizing the need to re-enter hazardous radioactive areas. Reducing entries decreases exposure, increases safety and minimizes waste.
Date: January 31, 2002
Creator: LeBaron, G. J.
Partner: UNT Libraries Government Documents Department
open access

2001 ''You Have the Power'' campaign [Federal Energy Management Program]. Final technical report

Description: The Tasks of 2001 ''You Have the Power'' campaign by the Federal Energy Management Program (FEMP) are: Task 1--Interagency Planning Meetings; Task 2--Ear Day Event; Task 3--Earth Day and Energy Awareness Month Activities; Task 4--Regional Target; Task 5--Outreach Tools and Campaign Products; Task 6--Private Sector Participation; Task 7--''You Have the Power'' on the FEMP Web Site; and Task 8--Effective Communications.
Date: January 1, 2002
Partner: UNT Libraries Government Documents Department
open access

21st Century Community Learning Centers: A History of the Program

Description: This report describes what Twenty-first Century Community Learning Centers (21st CCLC) are. The report also covers the reauthorization of funding for the program in 2002, how grants were awarded, and the essential questions Congress considered when reauthorizing the program. Moreover, the report includes the requirements 21st CCLC projects had to meet to receive the funds.
Date: January 22, 2002
Creator: McCallion, Gail
Partner: UNT Libraries Government Documents Department
open access

2nd Annual Los Alamos Plutonium Metal Standard Exchange Workshop : "preliminary" results

Description: The Rocky Flats Plutonium (Pu) Metal Sample Exchange program was conducted to insure the quality and intercomparability of measurements such as Pu assay, Pu isotopics, and impurity analyses. This program was discontinued in 1989 after more than 30 years. Los Alamos National Laboratory (LANL) has reestablished the Pu metal exchange program. During the first year, five DOE facilities, Argonne East, Argonne West, Livermore, Los Alamos, and New Brunswick Laboratory, Savannah River and the Atomic Weapons Establishment (AWE)' at Aldermaston are participating in the program. Plutonium metal samples are being prepared and distributed to the various sites primarily for destructive measurements for elemental concentration, isotopic abundance, and both metallic and nonmetallic impurity levels. The program is intended to provide independent verification of analytical measurement capability for each participating facility and to allow problems to be identified. Significants achievements in FY02 will be described. Results from category 1 elements and comparisons with Rocky Flats standards exchange metal historical data will also be presented. The roles and responsibilities of LANL and the external laboratories have been defined.
Date: January 1, 2002
Creator: Tandon, L. (Lav) & Slemmons, A. K. (Alice K.)
Partner: UNT Libraries Government Documents Department
open access

3D analysis of bainite morphologies and kinetics in alloy steels

Description: Serial sectioning and 3D reconstruction of austenite decomposition products were undertaken in bay-forming ternary steels to better understand their true morphologies in the bay region of their TTT diagrams. Jagged growth interfaces are revealed in allotriomorphic bainite formed at the bay in Fe-0.24C-4M0, contrasting with the idealized geometries often assumed when formulating growth models. This also has implications for experimental thickening kinetics measurments. Examination of the so-called 'degenerate' ferrite formed below the bay in Fe-Ox-6.3 W reveals that it is not degenerate at all, but rather has a Widmanstatten rod morphology which gives the appearance of degeneracy due to the multiplicity of ways that they can intersect a randomly-oriented plane of polish. Furthermore, these rods are grouped in packets posessing a common elongation direction, highlighting the crystallographic nature of their formation. The impact of these findings on the understanding of austenite decomposition in bayforming steels will be discussed.
Date: January 1, 2002
Creator: Hackenberg, R. E. (Robert E.); Nordstrom, D. P. (Dale P.) & Shiflet, G. J. (Gary J.)
Partner: UNT Libraries Government Documents Department
open access

Abu Sayyaf: Target of Philippine-U.S. Anti-Terrorism Cooperation

Description: This report provides an overview and policy analysis of the Abu Sayyaf terrorist group in the Philippines and the recently announced Philippine-U.S. program of military cooperation against it. It examines the origins and operations of Abu Sayyaf, the efforts of the Philippine government and military to eliminate it, and the implications of a greater U.S. military role in attempts to suppress it. The report will be updated periodically.
Date: January 25, 2002
Creator: Niksch, Larry A.
Partner: UNT Libraries Government Documents Department
open access

AC losses in prototype multistrand conductors for warm dielectric cable designs

Description: We report on multiphase ac losses in four-layer prototype multi-strand conductors (PMCs) wound from EITS tape provided by American Superconductor Corporation. These conductors are prototypes warm dielectric cable designs, such as for the US Dept. of Energy's Superconductivity Partnership Initiative Project at Detroit Edison, We report on single phase 'two phaset'(no current in Ihe PMC but with an external ac magnetic field generated by the two normal Conductors arranged at the remaining corners of an equilateral triangle forming a three-phase configuration) ,and balanced three phase losses. Losses were also measured using a set of saddle coils to apply an ac magnetic field to the PMC. The losses were measured as a function of temperature, frequency, and current. We compare the losses for three PMCs, one (4LA) wound conventionally with equal pitch angles for all layers and the two others (4LB and 4LC) wound to achieve equal current distribution (UCD) among the layers, and thus lower singlephase losses in the operating region. In addition, 4LC was wound with a newer gcneration tape having a higher critical current. The PMC 4LC was found to have the lowest single, twophase, and three-phase losses.
Date: January 1, 2002
Creator: Willis, Jeffrey O.; Maley, Martin P.; Boening, Henirch J.; Coletta, Giacomo; Mele, Renata & Nassi, Marco
Partner: UNT Libraries Government Documents Department
open access

Accurate quantification of radioactive materials by x-ray fluorescence : gallium in plutonium metal /.

Description: Two XRF specimen preparation methods were investigated for quantifying gallium in plutonium metal. Gallium in plutonium was chosen here as an example for demonstrating the efficacy of wavelength dispersive XRF for quantifying radioactive materials. The steps necessary to handle such materials safely will also be discussed. Quantification of plutonium samples by a well-established aqueous specimen preparation method resulted in relative precision and accuracy values of well less than 1%. As an alternative to the aqueous approach, a dried residue method was studied. Quantification of gallium in samples using this method resulted in relative precision and accuracy values an order of magnitude worse, but the method is faster, safer, and generates less waste than the aqueous process. The specimen preparation details and analysis results using each method will be presented here.
Date: January 1, 2002
Creator: Worley, C. G. (Christopher G.)
Partner: UNT Libraries Government Documents Department
open access

Active probing of cloud multiple scattering, optical depth, vertical thickness, and liquid water content using wide-angle imaging LIDAR.

Description: At most optical wavelengths, laser light in a cloud lidar experiment is not absorbed but merely scattered out of the beam, eventually escaping the cloud via multiple scattering. There is much information available in this light scattered far from the input beam, information ignored by traditional 'on-beam' lidar. Monitoring these off-beam returns in a fully space- and time-resolved manner is the essence of our unique instrument, Wide Angle Imaging Lidar (WAIL). In effect, WAIL produces wide-field (60-degree full-angle) 'movies' of the scattering process and records the cloud's radiative Green functions. A direct data product of WAIL is the distribution of photon path lengths resulting from multiple scattering in the cloud. Following insights from diffusion theory, we can use the measured Green functions to infer the physical thickness and optical depth of the cloud layer, and, from there, estimate the volume-averaged liquid water content. WAIL is notable in that it is applicable to optically thick clouds, a regime in which traditional lidar is reduced to ceilometry. Here we present recent WAIL data oti various clouds and discuss the extension of WAIL to full diurnal monitoring by means of an ultra-narrow magneto-optic atomic line filter for daytime measurements.
Date: January 1, 2002
Creator: Love, Steven P.; Davis, A. B. (Anthony B.); Rohde, C. A. (Charles A.); Tellier, L. L. (Larry L.) & Ho, Cheng,
Partner: UNT Libraries Government Documents Department
open access

Active probing of cloud thickness and optical depth using wide-angle imaging LIDAR.

Description: At most optical wavelengths, laser light in a cloud lidar experiment is not absorbed but merely scattered out of the beam, eventually escaping the cloud via multiple scattering. There is much information available in this light scattered far from the input beam, information ignored by traditional 'on-beam' lidar. Monitoring these off-beam returns in a fully space- and time-resolved manner is the essence of our unique instrument, Wide Angle Imaging Lidar (WAIL). In effect, WAIL produces wide-field (60{sup o} full-angle) 'movies' of the scattering process and records the cloud's radiative Green functions. A direct data product of WAIL is the distribution of photon path lengths resulting from multiple scattering in the cloud. Following insights from diffusion theory, we can use the measured Green functions to infer the physical thickness and optical depth of the cloud layer. WAIL is notable in that it is applicable to optically thick clouds, a regime in which traditional lidar is reduced to ceilometry. Section 2 covers the up-to-date evolution of the nighttime WAIL instrument at LANL. Section 3 reports our progress towards daytime capability for WAIL, an important extension to full diurnal cycle monitoring by means of an ultra-narrow magneto-optic atomic line filter. Section 4 describes briefly how the important cloud properties can be inferred from WAIL signals.
Date: January 1, 2002
Creator: Love, Steven P.; Davis, A. B. (Anthony B.); Rohde, C. A. (Charles A.); Tellier, L. L. (Larry L.) & Ho, Cheng,
Partner: UNT Libraries Government Documents Department
open access

Active vibration damping in the presence of uncertainties.

Description: Several control design techniques including PlD, LQG, and PPF are investigated For adive vibration damping of a cantilever beam with uncertain boundary conditions. Step disturbances were used to evaluate the performance of the designed controllers.
Date: January 1, 2002
Creator: Farrar, C. R. (Charles R.); Eisenhour, T. A. (Travis A.); Hatchett, S. (Sam) & Salazar, I. (Isaac)
Partner: UNT Libraries Government Documents Department
open access

Adaptive control in optical fibers

Description: Adpative control in combination with ultrafast pulse shaping provides a compelling approach to defeat dispersion, distortion and harness nonlinear phenomena on the femtosecond timescale. Ultrafast pulses propagating in optical fibers generate a number of linear and nonlinear effects which affect the pulse during its travel. The main causes stem from the dependence of the index of refraction on frequency (given that short pulses have a large bandwidth) and from the so-called self-action effects which involve the dependence of the index of refraction on the pulse intensity (which is high given that the pulse energy is confined to a very short amount of time).
Date: January 1, 2002
Creator: Omenetto, F. G. (Fiorenzo G.)
Partner: UNT Libraries Government Documents Department
open access

Adaptive Restoration of Airborne Daedalus AADS1268 ATM Thermal Data

Description: To incorporate the georegistration and restoration processes into airborne data processing in support of U.S. Department of Energy's nuclear emergency response task, we developed an adaptive restoration filter for airborne Daedalus AADS1268 ATM thermal data based on the Wiener filtering theory. Preliminary assessment shows that this filter enhances the detectability of small weak thermal anomalies in AADS1268 thermal images.
Date: January 1, 2002
Creator: Yuan, D.; Doak, E.; Guss, P. & Will, A.
Partner: UNT Libraries Government Documents Department
open access

Adaptive Tracking of Atmospheric Releases

Description: When dangerous chemical or biological releases occur in the atmosphere, emergency responders and decision makers must assess exposure rates to the affected population, establish evacuation routes, and allocate medical resources We have been working to improve the scientific basis for making such decisions. We believe that future rapid response teams, from LLNI, and other centers of expertise, will use a variety of atmospheric sensors and atmospheric computer models to predict and characterize the movement of chemical or biological releases in urban environments, and that LLNL is likely to contribute expertise in this area. A key advance will be to merge the information and capabilities of computer models with real-time atmospheric data from sensors. The resulting product will dynamically interpolate and extrapolate the raw sensor data into a coordinated ''picture'' or interpretation of the developing flow scenario. The scientific focus of the project was the exploration and development of algorithms to fuse lidar data (which measure wind speed much as a police radar measures vehicle speed) and a dispersion model into a single system. Our goal was to provide the scientific foundation for a combined lidar/model approach capable of accurately tracking the evolution of atmospheric releases on distance scales of about 20 km. The fundamental idea is to create feedbacks, so that lidar data can be used for wind field inputs into a dispersion model, which would, in turn, guide lidar data acquisition by directing more intensive scanning to regions where more data are key to improving the modeling. We created a database of synthetic lidar data that can be used to test algorithms relating to a combined lidar/dispersion model. We obtained the data, which represent nocturnal atmospheric drainage flows in the Salt Lake City Basin, from calculations on the LLNL ASCI White supercomputer with a computational fluid dynamics model running …
Date: January 31, 2002
Creator: Larson, D & Calhoun, R
Partner: UNT Libraries Government Documents Department
open access

Advanced characterization of twins using automated EBSD

Description: This poster describes resuns obtained using an automated, crystallographically-based technique for twin identification. The technique is based on the automated EBSD. The key features of the analysis are identification of potential twin boundaries by their misorientation character, identification of the distinct boundary planes among the symmetrically equiwlent candidates. and validation of these boundaries through comparison with the boundary and twin plane traces in the sample cross section. Results on the application of this technique to deformation twins in zirconium are analyzed for the effect of twin type and amount and sense of uniaxial deformation. The accumulation of strain tends to increase the misorientation deviation at least to the degree of the trace deviation compared with recrystalllzation twins in nickel.
Date: January 1, 2002
Creator: Wright, S. I. (Stuart I.); Bingert, J. F. (John F.); Mason, T. A. (Thomas A.) & Larsen, Ryan J.
Partner: UNT Libraries Government Documents Department
open access

Advanced characterization of twins using automated electron backscatter diffraction

Description: This paper describes results obtained using an automated, crystallographically-based technique for twin identification. The technique is based on the automated collection of spatially specific orientation measurements by electron backscatter diffraction (EBSD) in the scanning electron microscope (SEM). The key features of the analysis are identification of potential twin boundaries by their misorientation character, identification of the distinct boundary planes among the symmetrically equivalent candidates, and validation of these boundaries through comparison with the boundary and twin plane traces in the sample cross section. Results on the application of this technique to deformation twins in zirconium are analyzed for the effect of twin type and amount and sense of uniaxial deformation. The accumulation of strain tends to increase the misorientation deviation at least to the degree of the trace deviation compared with recrystallization twins in nickel. In addition to the results on characterizing the twin character, results on extending the twin analysis to automated identification of parent and daughter material for structures exhibiting twin deformation are reported as well.
Date: January 1, 2002
Creator: Wright, S. I. (Stuart I.); Bingert, J. F. (John F.); Mason, T. A. (Thomas A.) & Larson, R. J. (Ryan J.)
Partner: UNT Libraries Government Documents Department
open access

Advanced Cuttings Transport Study Quarterly Technical Report: October-December 2001

Description: This is the second quarterly progress report for Year 3 of the ACTS project. It includes a review of progress made in: (1) Flow Loop development and (2) research tasks during the period of time between Oct 1, 2001 and Dec. 31, 2001. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 3: Addition of a Cuttings Injection/Collection System), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (e) Research on instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), and Foam properties while transporting cuttings. (Task 12), (f) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.
Date: January 30, 2002
Creator: Reed, Troy; Miska, Stefan; Takach, Nicholas; Ashenayi, Kaveh; Kane, Gerald; Pickell, Mark et al.
Partner: UNT Libraries Government Documents Department
open access

ADVANCED FLUE GAS CONDITIONING AS A RETROFIT UPGRADE TO ENHANCE PM COLLECTION FROM COAL-FIRED ELECTRIC UTILITY BOILERS

Description: The U.S. Department of Energy and ADA Environmental Solutions are engaged in a project to develop commercial flue gas conditioning additives. The objective is to develop conditioning agents that can help improve particulate control performance of smaller or under-sized electrostatic precipitators on utility coal-fired boilers. The new chemicals will be used to control both the electrical resistivity and the adhesion or cohesivity of the fly ash. There is a need to provide cost-effective and safer alternatives to traditional flue gas conditioning with SO{sub 3} and ammonia. During this reporting quarter, installation of a flue gas conditioning system was completed at PacifiCorp Jim Bridger Power Plant. Performance testing was underway. Results will be detailed in the next quarterly and subsequent technical summary reports. Also in this quarter, discussions were initiated with a prospective long-term candidate plant. This plant fires a bituminous coal and has opacity performance issues related to fly ash re-entrainment. Ammonia conditioning has been proposed here, but there is interest in liquid additives as a safer alternative.
Date: January 1, 2002
Creator: Baldrey, Kenneth E.
Partner: UNT Libraries Government Documents Department
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