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Impact of the LHC beam abort kicker prefire on high luminosity insertion and CMS detector performance

Description: The effect of possible accidental beam loss in LHC on the IP5 insertion elements and CMS detector is studied via realistic Monte Carlo simulations. Such beam loss could be the consequence of an unsynchronized abort or � in worst case � an accidental prefire of one of the abort kicker modules. Simulations with the STRUCT code show that this beam losses would take place in the IP5 inner and outer triplets. MARS simulations of the hadronic and electro-magnetic cascades induced in such an event indicate severe heating of the inner triplet quadrupoles. In order to protect the IP5 elements, two methods are proposed: a set of shadow collimators in the outer triplet and a prefired module compensation using a special module charged with an opposite voltage (antikicker). The remnants of the accidental beam loss entering the experimental hall have been used as input for FLUKA simulations in the CMS detector. It is shown that it is vital to take measures to reliably protect the expensive CMS tracker components.
Date: April 13, 1999
Creator: A.I. Drozhdin, N.V. Mokhov and M. Huhtinen
Partner: UNT Libraries Government Documents Department
open access

FY06 LDRD Final Report Data Intensive Computing

Description: The goal of the data intensive LDRD was to investigate the fundamental research issues underlying the application of High Performance Computing (HPC) resources to the challenges of data intensive computing. We explored these issues through four targeted case studies derived from growing LLNL programs: high speed text processing, massive semantic graph analysis, streaming image feature extraction, and processing of streaming sensor data. The ultimate goal of this analysis was to provide scalable data management algorithms to support the development of a predictive knowledge capability consistent with the direction of Aurora.
Date: February 13, 2007
Creator: Abdulla, G M
Partner: UNT Libraries Government Documents Department
open access

Smart Grid Provisions in H.R. 6, 110th Congress

Description: This report provides an overview of Smart Grid, a distribution system that allows for flow of information from a customer's meter in two directions. It discusses both regulatory and technological barriers that have limited the implementation of Smart Grid technology.
Date: February 13, 2008
Creator: Abel, Amy
Partner: UNT Libraries Government Documents Department
open access

Electricity: The Road Toward Restructuring

Description: The Public Utility Holding Company Act of 1935 (PUHCA) and the Federal Power Act (FPA) were enacted to eliminate unfair practices and other abuses by electricity and gas holding companies by requiring federal control and regulation of interstate public utility holding companies. Comprehensive energy legislation has passed the House and Senate. The House passed H.R. 6 on April 11, 2003. On July 31, 2003, the Senate suspended debate on S. 14, inserted the text of H.R. 4 (107th Congress) as a substitute, and passed H.R. 6. A conference agreement was reached November 17, 2003, and passed by the House the next day. H.R. 6 includes an electricity title that would, in part, repeal PUHCA, would prospectively repeal the mandatory purchase requirement under PURPA, and would create an electric reliability organization. On June 15, 2004, H.R. 4503, a comprehensive energy policy bill, passed the House.
Date: May 13, 2003
Creator: Abel, Amy & Parker, Larry
Partner: UNT Libraries Government Documents Department
open access

State-by-State Comparison of Selected Electricity Restructuring Provisions

Description: Since 1996, twenty-one states have restructured their electricity markets. While the extent of this restructuring varies by state, four issues have generally been considered by all state legislatures: stranded costs, aggregation, universal service, and public benefits. This report compares the treatment of these issues in the restructuring legislation of the twenty-one states. Using information collected directly from the relevant state laws and the rules promulgated by state public utility commissions, this report provides a state-by-state comparison of the restructuring provisions relating to the four issues.
Date: January 13, 2000
Creator: Abel, Amy & Shimabukuro, Jon O.
Partner: UNT Libraries Government Documents Department
open access

MULTIDENTATE TEREPHTHALAMIDATE AND HYDROXYPYRIDONATE LIGANDS: TOWARDS NEW ORALLY ACTIVE CHELATORS

Description: The limitations of current therapies for the treatment of iron overload or radioisotope contamination have stimulated efforts to develop new orally bioavailable iron and actinide chelators. Siderophore-inspired tetradentate, hexadentate and octadentate terephthalamidate and hydroxypyridonate ligands were evaluated in vivo as selective and efficacious iron or actinide chelating agents, with several metal loading and ligand assessment procedures, using {sup 59}Fe, {sup 238}Pu, and {sup 241}Am as radioactive tracers. The compounds presented in this study were compared to commercially available therapeutic sequestering agents [deferoxamine (DFO) for iron and diethylenetriaminepentaacetic acid (DPTA) for actinides] and are unrivaled in terms of affinity, selectivity and decorporation efficacy, which attests to the fact that high metal affinity may overcome the low bioavailability properties commonly associated to multidenticity.
Date: July 13, 2011
Creator: Abergel, Rebecca J. & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department
open access

W and WSi(x) Ohmic Contacts on p- And n-Type GaN

Description: W and WSi ohmic contacts on both p- and n-type GaN have been annealed at temperatures from 300-1000 *C. There is minimal reaction (< 100 ~ broadening of the metal/GaN interface) even at 1000 *C. Specific contact resistances in the 10-5 f2-cm2 range are obtained for WSiX on Si-implanted GaN with a peak doping concentration of- 5 x 1020 cm-3, after annealing at 950 `C. On p-GaN, leaky Schottky diode behavior is observed for W, WSiX and Ni/Au contacts at room temperature, but true ohmic characteristics are obtained at 250 - 300 *C, where the specific contact resistances are typically in the 10-2 K2-cm2 range. The best contacts for W and WSiX are obtained after 700 *C annealing for periods of 30- 120 sees. The formation of &WzN interracial phases appear to be important in determining the contact quality.
Date: October 13, 1998
Creator: Abernathy, C.R.; Cao, X.A.; Eizenberg, M.; Han, J.; Lothian, J.R.; Pearton, S.J. et al.
Partner: UNT Libraries Government Documents Department
open access

Facet Model and Mathematical Morphology for Surface Characterization

Description: This paper describes an algorithm for the automatic segmentation and representation of surface structures and non-uniformities in an industrial setting. The automatic image processing and analysis algorithm is developed as part of a complete on-line web characterization system of a papermaking process at the wet end. The goal is to: (1) link certain types of structures on the surface of the web to known machine parameter values, and (2) find the connection between detected structures at the beginning of the line and defects seen on the final product. Images of the pulp mixture (slurry), carried by a fast moving table, are obtained using a stroboscopic light and a CCD camera. This characterization algorithm succeeded where conventional contrast and edge detection techniques failed due to a poorly controlled environment. The images obtained have poor contrast and contain noise caused by a variety of sources. After a number of enhancement steps, conventional segmentation methods still f ailed to detect any structures and are consequently discarded. Techniques tried include the Canny edge detector, the Sobel, Roberts, and Prewitt's filters, as well as zero crossings. The facet model algorithm, is then applied to the images with various parameter settings and is found to be successful in detecting the various topographic characteristics of the surface of the slurry. Pertinent topographic elements are retained and a filtered image computed. Carefully tailored morphological operators are then applied to detect and segment regions of interest. Those regions are then selected according to their size, elongation, and orientation. Their bounding rectangles are computed and represented. Also addressed in this paper are aspects of the real time implementation of this algorithm for on-line use. The algorithm is tested on over 500 images of slurry and is found to segment and characterize nonuniformities on all 500 images.
Date: November 13, 1999
Creator: Abidi, B.R.; Goddard, J.S.; Hunt, M.A. & Sari-Sarraf, H.
Partner: UNT Libraries Government Documents Department
open access

Corrosion behavior of stainless steel-zirconium alloy waste forms.

Description: Stainless steel-zirconium (SS-Zr) alloys are being considered as waste forms for the disposal of metallic waste generated during the electrometallurgical treatment of spent nuclear fuel. The baseline waste form for spent fuels from the EBR-II reactor is a stainless steel-15 wt.% zirconium (SS-15Zr) alloy. This article briefly reviews the microstructure of various SS-Zr waste form alloys and presents results of immersion corrosion and electrochemical corrosion tests performed on these alloys. The electrochemical tests show that the corrosion behavior of SS-Zr alloys is comparable to those of other alloys being considered for the Yucca Mountain geologic repository. The immersion tests demonstrate that the SS-Zr alloys are resistant to selective leaching of fission product elements and, hence, suitable as candidates for high-level nuclear waste forms.
Date: January 13, 1999
Creator: Abraham, D. P.
Partner: UNT Libraries Government Documents Department
open access

Partition of solutes from the gas phase and from water to wet and dry di-n-butyl ether: a linear free energy relationship analysis

Description: Article on the partition of solutes from the gas phase and from water to wet and dry di-n-butyl ether and a linear free energy relationship analysis.
Date: August 13, 2001
Creator: Abraham, M. H. (Michael H.); Zissimos, Andreas M. & Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences
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