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1.2 MW klystron for Asymmetric Storage Ring B Factory

Description: A cw klystron operating at 476 MHz has been developed jointly by SLAC and Varian Associates. The unique set of characteristics of this tube were strongly guided by requirements of the fast feedback necessary to prevent oscillations of the storage ring beams caused by the detuned accelerating cavity. This requires a combination of bandwidth and short group delay within the klystron. The RF feedback stabilization scheme also requires amplitude modulation making it necessary to operate the klystron about 10% below saturation. Performance specifications and initial operating results are presented.
Date: March 1995
Creator: Fowkes, W. R.; Caryotakis, G. & Doyle, E.
open access

A 1.5 GeV compact light source with superconducting bending magnets

Description: This paper describes the design of a compact electron synchrotron light source for producing X-rays for medical imaging, protein crystallography, nano-machining and other uses up to 35 keV. The source will provide synchrotron light from six 6.9 tesla superconducting 60{degree} bending magnet stations. In addition the ring, contains conventional quadrupoles and sextupoles. The light source has a circumference of 26 meters, which permits it to be located in a variety of industrial and medical facilities.
Date: May 1995
Creator: Garren, A. A.; Cline, D. B.; Kolonko, J. J.; Green, M. A.; Johnson, D. E.; Leung, E. M. et al.
open access

2-D image segmentation using minimum spanning trees

Description: This paper presents a new algorithm for partitioning a gray-level image into connected homogeneous regions. The novelty of this algorithm lies in the fact that by constructing a minimum spanning tree representation of a gray-level image, it reduces a region partitioning problem to a minimum spanning tree partitioning problem, and hence reduces the computational complexity of the region partitioning problem. The tree-partitioning algorithm, in essence, partitions a minimum spanning tree into subtrees, representing different homogeneous regions, by minimizing the sum of variations of gray levels over all subtrees under the constraints that each subtree should have at least a specified number of nodes, and two adjacent subtrees should have significantly different average gray-levels. Two (faster) heuristic implementations are also given for large-scale region partitioning problems. Test results have shown that the segmentation results are satisfactory and insensitive to noise.
Date: September 1995
Creator: Xu, Y. & Uberbacher, E. C.
open access

N = 2 string amplitudes

Description: In physics, solvable models have played very important roles. Understanding a simple model in detail teaches us a lot about more complicated models in generic situations. Five years ago, C. Vafa and I found that the closed N = 2 string theory, that is a string theory with the N = 2 local supersymmetry on the worldsheet, is classically equivalent to the self-dual Einstein gravity in four spacetime dimensions. Thus this string theory is solvable at the classical level. More recently, we have examined the N = 2 string partition function for spacial compactifications, and computed it to all order in the string perturbation expansion. The fact that such computation is possible at all suggests that the N = 2 string theory is solvable even quantum mechanically.
Date: August 1, 1995
Creator: Ooguri, H.
open access

2 {times} 2 TeV {mu}{sup +}{mu}{sup {minus}} collider: Lattice and accelerator-detector interface study

Description: The design for a high-luminosity {mu}{sup +}{mu}{sup {minus}} superconducting storage ring is presented based on first-pass calculations. Special attention is paid to two Iowa interaction regions (IR) whose optics are literally interlaced with the collider detectors. Various sources of backgrounds in IR are explored via realistic Monte Carlo simulations. An improved design of the collider lattice in the neighborhood of the interaction points (EP) is determined by the need to reduce significantly background levels in the detectors.
Date: May 1, 1995
Creator: Gelfand, N. M. & Mokhov, N. V.
open access

3-D field computation: The near-triumph of commerical codes

Description: In recent years, more and more of those who design and analyze magnets and other devices are using commercial codes rather than developing their own. This paper considers the commercial codes and the features available with them. Other recent trends with 3-D field computation include parallel computation and visualization methods such as virtual reality systems.
Date: July 1995
Creator: Turner, L. R.
open access

A 3-D numerical study of pinhole diffraction to predict the accuracy of EUV point diffraction interferometry

Description: A 3-D electromagnetic field simulation is used to model the propagation of extreme ultraviolet (EUV), 13-nm, light through sub-1500 {Angstrom} dia pinholes in a highly absorptive medium. Deviations of the diffracted wavefront phase from an ideal sphere are studied within 0.1 numerical aperture, to predict the accuracy of EUV point diffraction interferometersused in at-wavelength testing of nearly diffraction-limited EUV optical systems. Aberration magnitudes are studied for various 3-D pinhole models, including cylindrical and conical pinhole bores.
Date: December 1, 1995
Creator: Goldberg, K.A.; Tejnil, E. & Bokor, J.
open access

3-D Seismic Imaging of Complex Geologies

Description: We present three codes for the Intel Paragon that address the problem of three-dimensional seismic imaging of complex geologies. The first code models acoustic wave propagation and can be used to generate data sets to calibrate and validate seismic imaging codes. This code reported the fastest timings for acoustic wave propagation codes at a recent SEG (Society of Exploration Geophysicists) meeting. The second code implements a Kirchhoff method for pre-stack depth migration. Development of this code is almost complete, and preliminary results are presented. The third code implements a wave equation approach to seismic migration and is a Paragon implementation of a code from the ARCO Seismic Benchmark Suite.
Date: February 1, 1995
Creator: Womble, David E.; Dosanjh, Sudip S.; VanDyke, John P.; Oldfield, Ron A. & Greenberg, David S.
open access

3-D woven, mullite matrix, composite filter

Description: Westinghouse, with Techniweave as a major subcontractor, is conducting a three-phase program aimed at providing advanced candle filters for a 1996 pilot scale demonstration in one of the two hot gas filter systems at Southern Company Service`s Wilsonville PSD Facility. The Base Program (Phases I and II) objective is to develop and demonstrate the suitability of the Westinghouse/Techniweave next generation composite candle filter for use in Pressurized Fluidized Bed Combustion (PFBC) and/or Integrated Gasification Combined Cycle (IGCC) power generation systems. The Optional Task (Phase M, Task 5) objective is to fabricate, inspect and ship to Wilsonville Hot gas particulate filters are key components for the successful commercializaion of advanced coal-based power-generation systems such as Pressurized Fluidized-bed Combustion (PFBC), including second-generation PFBC, and Integrated Gasification Combined Cycles (IGCC). Current generation monolithic ceramic filters are subject to catastrophic failure because they have very low resistance to crack propagation. To overcome this problem, a damage-tolerant ceramic filter element is needed.
Date: December 1, 1995
Creator: Lane, J. E.; Painter, C. J.; Radford, K. C. & LeCostaouec, J. F.
open access

4 MW upgrade to DIII-D FWCD system: System commissioning and initial operation

Description: The initial installation of the 4 MW fast wave current drive (FWCD) upgrade started in 1992 with the purchase of two ABB/Thomcast AG rf power amplifiers. These amplifiers cover the frequency range 30 MHz to 120 MHz. A maximum output power of over 2 MW between 30 MHz and 80 MHz and 1 MW at 120 MHz were the specification requirements. The system as installed is comprised of the two mentioned rf amplifiers, coaxial transmission and matching components, rf phase and amplitude monitoring, and a SUN SparcStation 10 control system. Due to various reasons almost every major component in the system required redesign and engineering in order to meet the system requirements. The failures, probable cause and the final redesigns will be discussed as well as some thoughts on how better to specify system requirements for future systems.
Date: October 1995
Creator: Cary, W. P.; Callis, R. W.; de Grassie, J. S.; Harris, T. E.; O`Neill, R. C.; Pinsker, R. I. et al.
open access

5. international workshop on the identification of transcribed sequences

Description: This workshop was held November 5--8, 1995 in Les Embiez, France. The purpose of this conference was to provide a multidisciplinary forum for exchange of state-of-the-art information on mapping the human genome. Attention is focused on the following topics: transcriptional maps; functional analysis; techniques; model organisms; and tissue specific libraries and genes. Abstracts are included of the papers that were presented.
Date: December 31, 1995
open access

A 6.3 T Bend Magnet for the Advanced Light Source

Description: The Advanced Light Source (ALS) is a 1.5 to 1.9 GeV high-brightness electron storage ring operating at Lawrence Berkeley Laboratory (LBL) that provides synchrotron radiation for a large variety of users. It Is proposed to replace three of the thirty six 1.5T, one meter long bend magnets with very sbort high-field superconductlng (SC) dipoles. These magnets would provide bend-magnet synchrotron radiation to six bcamlines with a critical energy of at least 6 keV that is much better suited for protein crystallography and other small-sample x-ray diffraction and adsorption studies, than is currently available at the ALS. The magnet design is described, including coil, yoke, magnetic field analysis, and cyrostat. A prototype magnet is under construction at LBL.
Date: June 7, 1995
Creator: Taylor, C. E. & Caspi, S.
open access

The 8-GeV transfer line injection into main ring

Description: Included in this report are a brief review of the design lattice of the 8-GeV beam transfer line and the Main Ring, the recent measurements on the 8-GeV line lattice function as well as that of the Main Ring at 8-GeV. The injection matching is a very important part of the MR operation. Mismatches such as energy, timing, or position are easily corrected because they cause oscillations which are visible on the Turn-By-Turn (TBT) TV monitor display. Mis-matches due to beta and dispersion functions are detected only by using the Flying Wire or by doing measurements during beam study. A new method which makes use of the available data from TBT hardware was used to obtain the beam phase space ellipse. Data taken from Main Ring at injection gives the beta function needed for transfer matching from 8-GeV line. The result of this measurement is also presented here.
Date: June 1, 1995
Creator: Yang, M. J.
open access

9. international mouse genome conference

Description: This conference was held November 12--16, 1995 in Ann Arbor, Michigan. The purpose of this conference was to provide a multidisciplinary forum for exchange of state-of-the-art information on genetic mapping in mice. This report contains abstracts of presentations, focusing on the following areas: mutation identification; comparative mapping; informatics and complex traits; mutagenesis; gene identification and new technology; and genetic and physical mapping.
Date: December 31, 1995
open access

10 CFR 830.120 Criterion 10, Independent Assessment: We`re here to help you!

Description: Each organization performing activities in the DOE Weapons Complex is required to have an pendent assessment function. This is consistent from DOE Order 5700.6C, Quality Assurance to 10 CFR 830-120, sometimes referred to as the Price-Anderson rule. DOE Order 5700.6C, Criterion 10 Independent Assessment requires, `` Planned and periodic independent assessments shall be conducted to measure item quality and process effectiveness and to promote improvement. The organization performing independent assessments shall have sufficient authority and freedom from the line organization to carry out its responsibilities. Persons conducting independent assessments shall be technically qualified and knowledgeable in the areas assessed.`` 10 CFR 830.120, (c) Quality assurance criteria -- (3) Assessment -- (ii) Independent Assessment requires,``Independent assessments shall be planned and conducted to measure item and service quality, to measure the adequacy of work performance, and to promote improvement. The group performing independent assessments shall have sufficient authority and freedom from the line to carry out its responsibilities. Persons conducting independent assessments shall be technically qualified and knowledgeable in the areas assessed.``
Date: July 1, 1995
Creator: Farrell, R.E.
open access

A 10-GeV, 5-MW proton source for a muon-muon collider

Description: The performance parameters of a proton source which produces the required flux of muons for a 2-TeV on 2-TeV muon collider are: a beam energy of 10 GeV, a repetition rate of 30 Hz, two bunches per pulse with 5 x 10{sup 13} protons per bunch, and an rms bunch length of 3 nsec (1). Aside from the bunch length requirement, these parameters are identical to those of a 5-MW proton source for a spallation neutron source based on a 10-GeV rapid cycling synchrotron (RCS) (2). The 10-GeV synchrotron uses a 2-GeV accelerator system as its injector, and the 2-GeV RCS is an extension of a feasibility study for a I-MW spallation source described elsewhere (3--9). A study for the 5-MW spallation source was performed for ANL site-specific geometrical requirements. Details are presented for a site-independent proton source suitable for the muon collider utilizing the results of the 5-MW spallation source study.
Date: December 31, 1995
Creator: Cho, Y.; Chae, Y.-C. & Crosbie, E.
open access

A 10-GeV, 5-MW proton source for a pulsed spallation source

Description: A feasibility study for a pulsed spallation source based on a 5-MW, 10-GeV rapid proton synchrotron (RCS) is in progress. The integrated concept and performance parameters of the facility are discussed. The 10-GeV synchrotron uses as its injector the 2-GeV accelerator system of a 1-MW source described elsewhere. The 1-MW source accelerator system consists of a 400-MeV H{sup {minus}} linac with 2.5 MeV energy spread in the 75% chopped (25% removed) beam and a 30-Hz RCS that accelerates the 400-MeV beam to 2 GeV. The time averaged current of the accelerator system is 0.5 mA, equivalent to 1.04 {times} 10{sup 14} protons per pulse. The 10-GeV RCS accepts the 2 GeV beam and accelerates it to 10 GeV. Beam transfer from the 2-GeV synchrotron to the 10-GeV machine u highly efficient bunch-to-bucket injection, so that the transfer can be made without beam loss. The synchrotron lattice uses FODO cells of 90{degrees} phase advance. Dispersion-free straight sections are obtained using a missing magnet scheme. The synchrotron magnets are powered by dual-frequency resonant circuits. The magnets are excited at a 20-Hz rate and de-excited at 60-Hz. resulting in an effective 30-Hz rate. A key feature of the design of this accelerator system is that beam losses are minimized from injection to extraction, reducing activation to levels consistent with hands-on maintenance. Details of the study are presented.
Date: December 31, 1995
Creator: Cho, Y.; Chae, Y.C. & Crosbie, E.
open access

10-MW demonstration of the gas suspension absorption process at TVA`s Center for Emissions Research. Final report

Description: The Tennessee Valley Authority (TVA) in cooperation with AirPol Inc., and the U.S. Department of Energy (DOE), has recently completed a successful 17-month test program with the AirPol Gas Suspension Absorption (GSA) flue gas desulfurization (FGD) process at TVA`s Center for Emissions Research (CER). This project was selected by DOE for funding in the third round of the Clean Coal Technology Program. This 10-MW demonstration of the GSA FGD system at the CER was the first application of this technology in the U.S. The GSA test program, which was cofunded two-thirds by TVA and one-third by DOE/AirPol, was completed over a 17-month period from November 1, 1992 to March 31, 1993. This test program demonstrated that the GSA FGD technology could achieve high SO{sub 2} removal efficiencies (90+ percent) for a 2.7 percent sulfur (as-fired) coal application, while maintaining particulate emissions below the New Source Performance Standards (NSPS), i.e., 0.03 lb/MBtu, in a four-field electrostatic precipitator. The reliability and operability of this system was also demonstrated in a 28-day, 24 hour/day, continuous run during which the GSA unit simultaneously achieved high SO{sub 2} removal efficiencies (90+ percent) and maintained particulate emissions below the NSPS. Also, the air toxics removal capabilities of the GSA system were determined in a series of tests. A 1-MW pulsejet baghouse (PJBH) pilot plant was also tested in conjunction with this GSA test program. This PJBH testing was initially cofunded by TVA and the Electric Power Research Institute, who were later joined by AirPol and DOE in sponsoring this PJBH testing. A 14-day PJBH demonstration run was also completed to confirm the reliability of this system.
Date: March 1995
open access

12 Batch coalescing studies

Description: The purpose of the study was to identify and correct the problems in the 12 batch coalescing. The final goal is to be able to coalesce 12 booster batches of 11 bunches each into 12 bunches spaced at 21 buckets apart with an average intensity of 200 E9 ppb.
Date: January 1, 1995
Creator: Kourbanis, I. & Wildman, D.
open access

15. International Conference on Plant Growth Substances: Program -- Abstracts

Description: Since the 14th Conference in Amsterdam in 1991, progress in plant hormone research and developmental plant biology has been truly astonishing. The five ``classical`` plant hormones, auxin, gibberellin, cytokinin, ethylene, and abscisic acid, have been joined by a number of new signal molecules, e.g., systemin, jasmonic acid, salicylic acid, whose biosynthesis and functions are being understood in ever greater detail. Molecular genetics has opened new vistas in an understanding of transduction pathways that regulate developmental processes in response to hormonal and environmental signals. The program of the 15th Conference includes accounts of this progress and brings together scientists whose work focuses on physiological, biochemical, and chemical aspects of plant growth regulation. This volume contains the abstracts of papers presented at this conference.
Date: December 31, 1995
open access

A 30-T pulsed magnet suitable for neutron scattering experiments

Description: We describe a conceptual design for a 30-T vertical-field split-pair magnet suitable for neutron scattering studies. While the magnet is primarily intended for diffraction and spectroscopic studies using a pulsed neutron source, it might also have application for relaxational studies,at steady-state sources. The magnet will have a 5-cm bore for sample environment equipment, a 1-cm gap for the neutrons to illuminate the sample and through which to observe the scattering. It will run with a repetition frequency of 2 Hz, and a pulse length of 3 ms. We discuss scientific and engineering considerations that led to this specification and describe the designs of both magnet and power supply.
Date: July 1, 1995
Creator: Robinson, R. A.; Boenig, H. J.; Eyssa, Y. M. & Schneider-Muntau, H. J.
open access

45-day safety screen results and final report for tank 241-C-202, auger samples 95-Aug-026 and 95-Aug-027

Description: Two auger samples from tank 241-C-202 (C-202) were received at the 222-S Laboratories and underwent safety screening analysis, consisting of differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and total alpha activity. Two samples were submitted for energetics determination by DSC. Within the triplicate analyses of each sample, one of the results for energetics exceeded the notification limit. The sample and duplicate analyses for both augers exceeded the notification limit for TGA. As required by the Tank Characterization Plan, the appropriate notifications were made within 24 hours of official confirmation that the limits were violated.
Date: June 19, 1995
Creator: Baldwin, J.H.
open access

45-day safety screen results and final report for Tank 241-C-203, Auger samples 95 AUG-020 and 95-AUG-021

Description: This document serves as the 45-day report deliverable for the tank C-203 auger samples collected on April 5, 1995 (samples 95-AUG-20 and 95-AUG-021). As no secondary analyses were required and no other analyses have been requested, this document also serves as the final report for C-203 auger sampling. Each sample was received, extruded, and analyzed by the 222-S Laboratories in accordance with the Tank Characterization Plan (TCP) referenced below. Included in this report are the primary safety screening results (DSC, TGA, and alpha) and density results. The worklists and raw data are included in this report. Photographs of the auger samples were taken during extrusion and, although not included in this report, are available.
Date: May 18, 1995
Creator: Conner, J.M.
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