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Science and Technology Review June 2005

Description: This is the articles in this month's issue: (1) Close Collaborations Advance Progress in Genomic Research--Commentary by Elbert Branscomb; (2) Mining Genomes--Livermore computer programs help locate the stretches of DNA in gene deserts that regulate protein-making genes; (3) Shedding Light on Quantum Physics--Laboratory laser research builds from the foundation of Einstein's description of the quantization of light. (4) The Sharper Image for Surveillance--Speckle imaging-an image-processing tec… more
Date: May 3, 2005
Creator: Aufderheide, M
Item Type: Refine your search to only Report
open access

Analysis of Fabry-Perot Velocimeter Records

Description: Program demonstration and user instructions are presented for FabryVB5. This computer program was created for use in analyzing Fabry-Perot interferometer records that detail the velocity time histories of fast moving surfaces. Graphical curves representing peak fringe positions and fiducial timing dots are extracted from a digitized film record or from a CCD digital image. An analysis is demonstrated on a sample velocimeter record along with some mathematical formula and routine operations. Rou… more
Date: August 3, 2001
Creator: Avara, G.
Item Type: Refine your search to only Report
open access

Mid infrared observations of Van Maanen 2: no substellar companion.

Description: The results of a comprehensive infrared imaging search for the putative 0.06 M{sub {circle_dot}} astrometric companion to the 4.4 pc white dwarf van Mannen 2 are reported. Adaptive optics images acquired at 3.8 {micro}m reveal a diffraction limited core of 0.09 inch and no direct evidence of a secondary. Models predict that at 5 Gyr, a 50 M{sub J} brown dwarf would be only 1 magnitude fainter than van Maanen 2 at this wavelength and the astrometric analysis suggested a separation of 0.2 inch. I… more
Date: November 3, 2004
Creator: Farihi, J; Becklin, E & Macintosh, B
Item Type: Refine your search to only Article
open access

Reviewers Comments on the 5th Symposium and the Status of Fusion Research 2003

Description: Better to understand the status of fusion research in the year 2003 we will first put the research in its historical context. Fusion power research, now beginning its sixth decade of continuous effort, is unique in the field of scientific research. Unique in its mixture of pure and applied research, unique in its long-term goal and its promise for the future, and unique in the degree that it has been guided and constrained by national and international governmental policy. Though fusion researc… more
Date: February 3, 2005
Creator: Post, R F
Item Type: Refine your search to only Article
open access

Hyperspectral Mineral Mapping in Support of Geothermal Exploration: Examples from Long Valley Caldera, CA and Dixie Valley, NV, USA

Description: Growing interest and exploration dollars within the geothermal sector have paved the way for increasingly sophisticated suites of geophysical and geochemical tools and methodologies. The efforts to characterize and assess known geothermal fields and find new, previously unknown resources has been aided by the advent of higher spatial resolution airborne geophysics (e.g. aeromagnetics), development of new seismic processing techniques, and the genesis of modern multi-dimensional fluid flow and s… more
Date: March 3, 2004
Creator: Pickles, W. L.; Martini, B. A.; Silver, E. A. & Cocks, P. A.
Item Type: Refine your search to only Article
open access

Seismic Velocities Contain Information About Depth, Lithology, Fluid Content, and Microstructure

Description: Recent advances in field and laboratory methods for measuring elastic wave velocities provide incentive and opportunity for improving interpretation of geophysical data for engineering and environmental applications. Advancing the state-of-the-art of seismic imaging requires developing petrophysical relationships between measured velocities and the hydrogeology parameters and lithology. Our approach uses laboratory data and rock physics methods. Compressional (Vp) and shear (Vs) wave velocities… more
Date: January 3, 2002
Creator: Berge, P A & Bonner, B P
Item Type: Refine your search to only Article
open access

Implicit Occluders

Description: In this paper we propose a novel visibility-culling technique for optimizing the computation and rendering of opaque isosurfaces. Given a continuous scalar field f (x) over a domain D and an isovalue w, our technique exploits the continuity of f to determine conservative visibility bounds implicitly, i.e., without the need for actually computing the isosurface f{sup -1}(w). We generate Implicit Occluders based on the change in sign of f *(x) = f (x)-w, from positive to negative (or vice versa) … more
Date: February 3, 2004
Creator: Pesco, S; Lindstrom, P; Pascucci, V & Silva, C T
Item Type: Refine your search to only Article
open access

Passive Seismic Monitoring for Rockfall at Yucca Mountain: Concept Tests

Description: For the purpose of proof-testing a system intended to remotely monitor rockfall inside a potential radioactive waste repository at Yucca Mountain, a system of seismic sub-arrays will be deployed and tested on the surface of the mountain. The goal is to identify and locate rockfall events remotely using automated data collecting and processing techniques. We install seismometers on the ground surface, generate seismic energy to simulate rockfall in underground space beneath the array, and interp… more
Date: March 3, 2003
Creator: Cheng, J.; Twilley, K.; Murvosh, H.; Tu, Y.; Luke, B.; Yfantis, A. et al.
Item Type: Refine your search to only Article
open access

Sheath Physics and Boundary Conditions for Edge Plasmas

Description: The boundary conditions of mass, momentum, energy, and charge appropriate for fluid formulations of edge plasmas are surveyed. We re-visit the classic problem of 1-dimensional flow, and note that the ''Bohm sheath criterion'' is requirement of connectivity of the interior plasma with the external world, not the result of termination of the plasma by a wall. We show that the nature of the interior plasma solution is intrinsically different for ion sources that inject above and below the electron… more
Date: September 3, 2003
Creator: Cohen, R. H. & Ryutov, D. D.
Item Type: Refine your search to only Article
open access

LORENTZ PHASE IMAGING AND IN-SITU LORENTZ MICROSCOPY OF PATTERNED CO-ARRAYS.

Description: Understanding magnetic structures and properties of patterned and ordinary magnetic films at nanometer length-scale is the area of immense technological and fundamental scientific importance. The key feature to such success is the ability to achieve visual quantitative information on domain configurations with a maximum ''magnetic'' resolution. Several methods have been developed to meet these demands (Kerr and Faraday effects, differential phase contrast microscopy, magnetic force microscopy, … more
Date: August 3, 2003
Creator: VOLKOV,V. V. ZHU,Y.
Item Type: Refine your search to only Article
open access

Arsenic Mobilization from Contaminated Sediments: A Full-scale Experiment in Progress

Description: The mobilization of arsenic was examined in a system where the deposition of iron and arsenic have been substantially modified by large-scale manipulations. This engineering practice was designed to decrease arsenic concentrations in water supplied to the City of Los Angeles. Accomplishing this objective, however, has resulted in significant accumulation of arsenic and iron in the sediments of a reservoir on the Los Angeles Aqueduct. Arsenic and iron are released into the porewater at depth in … more
Date: February 3, 2004
Creator: O'Day, P A; Campbell, K; Dixit, S & Hering, J G
Item Type: Refine your search to only Article
open access

Designers Workbench: Towards Real-Time Immersive Modeling

Description: This paper introduces the DesignersWorkbench, a semi-immersive virtual environment for two-handed modeling, sculpting and analysis tasks. The paper outlines the fundamental tools, design metaphors and hardware components required for an intuitive real-time modeling system. As companies focus on streamlining productivity to cope with global competition, the migration to computer-aided design (CAD), computer-aided manufacturing (CAM), and computer-aided engineering (CAE) systems has established a… more
Date: October 3, 2001
Creator: Kuester, F; Duchaineau, M A; Hamann, B; Joy, K I & Ma, K L
Item Type: Refine your search to only Article
open access

Photometric Calibration of an EUV Flat Field Spectrometer at the Advanced Light Source

Description: The photometric calibration of ail extreme ultraviolet flat field spectrometer has been done at the Advanced Light Source at LBNL. This spectrometer is used to record spectrum for atomic physics research from highly charged ions in plasmas created in the Livermore electron beam ion traps EBIT-I and SUPEREBIT. Two calibrations were done each with a different gold-coated grating, a 1200 {ell}/mm and a 2400 {ell}/mm, that covered 75-300{angstrom} and 15-160{angstrom}, respectively. The detector fo… more
Date: July 3, 2002
Creator: May, M.; Lepson, J.; Beiersdorfer, P.; Thorn, D.; Chen, H.; Hey, D. et al.
Item Type: Refine your search to only Article
open access

Results from the First {sup 249}Cf + {sup 48}Ca Experiment

Description: The present paper reports the results of an attempt aimed at the synthesis of element 118 in the reaction {sup 249}Cf({sup 48}Ca,3n){sup 294}118. The experiment was performed employing the Dubna Gas-filled Recoil Separator and the U400 heavy-ion cyclotron at FLNR, JINR, Dubna. In the course of a 2300-hour irradiation of an enriched {sup 249}Cf target (0.23 mg/cm{sup 2}) with a beam of 245-MeV {sup 48}Ca ions, we accumulated a total beam dose of 2.5 x 10{sup 19} ions. We detected two events that… more
Date: February 3, 2003
Creator: Oganessian, Y T; Utyonkov, V K; Lobanov, Y V; Abdullin, F S; Polyakov, A N; Shirokovsky, I V et al.
Item Type: Refine your search to only Report
open access

Properties of Fluid Deuterium under Double-Shock Compression to Several Mbar

Description: The compressibility of fluid deuterium up to several Mbar has been probed using laser-driven shock waves reflected from a quartz anvil. Combining high-precision ({approx} 1 %) shock velocity measurements with the double-shock technique, where differences in equation of state (EOS) models are magnified, has allowed us to accurately discriminate between various theoretical predictions. Our data are consistent with EOS models that show approximately fourfold compression on the principal Hugoniot f… more
Date: February 3, 2004
Creator: Vianello, E; Celliers, P M; Hicks, D G; Boehly, T R; Collins, T B; Moon, S J et al.
Item Type: Refine your search to only Article
open access

Science and Technology and Counterterorrism

Description: Major scientific and technological breakthroughs played a pivotal role in our ability to win the Cold War. The possibility of a different type of war, in response to terrorism, has long been recognized. Indeed, countermeasures to address specific terrorist acts have been developed and are deployed, for example, at special sporting and political events. The current threat environment, however, has created an intense and compelling set of concerns; consequently, the challenge to the scientific Co… more
Date: April 3, 2002
Creator: Wadsworth, J
Item Type: Refine your search to only Article
open access

Many amino acid substitution variants identified in DNA repair genes during human population screenings are predicted to impact protein function

Description: Over 520 different amino acid substitution variants have been previously identified in the systematic screening of 91 human DNA repair genes for sequence variation. Two algorithms were employed to predict the impact of these amino acid substitutions on protein activity. Sorting Intolerant From Tolerant (SIFT) classified 226 of 508 variants (44%) as ''Intolerant''. Polymorphism Phenotyping (PolyPhen) classed 165 of 489 amino acid substitutions (34%) as ''Probably or Possibly Damaging''. Another … more
Date: November 3, 2003
Creator: Xi, T; Jones, I M & Mohrenweiser, H W
Item Type: Refine your search to only Article
open access

Biased deposition of nanocrystalline Be1-x Cux coatings

Description: Coatings of Be{sub 1-x}Cu{sub x} are prepared by magnetron sputter deposition onto spherical polymer mandrels. The application of an applied bias during deposition refines the columnar morphology of the coating and surface finish to the nanoscale. A mechanical testing technique is developed to load the thin-walled spherical capsules under uniaxial tension at constant strain to fracture. The bias-deposited material exhibits an increase in strength by a factor of three or more following a Hall-Pe… more
Date: November 3, 2000
Creator: Jankowski, Alan Frederic
Item Type: Refine your search to only Article
open access

Theoretical Model for the EM Effects Induced by High-Energy Photons (Gamma, X-ray) in Dielectric Materials and Electronic Systems

Description: During last twenty years, a number of models have been used to calculate the change of conductivity and dielectric strength in materials caused by the passage of high-energy photons, such as Gamma-rays and X-rays. In these models, the electromagnetic fields generated in the electronic system created by the high-energy photons have not been investigated. That is, the solution of Maxwell's equations has not been obtained for these kinds of problems. We constructed a theoretical model, described b… more
Date: August 3, 2001
Creator: Yee, J H; Mayhall, D J & Bland, M F
Item Type: Refine your search to only Report
open access

RadHeat V1 User's Manual

Description: RadHeat is a one dimensional finite difference heat transfer code that can determine the transient temperature evolution of layered targets in pulsed penetrating radiation environments. It makes use of energy dependent opacity and stopping data to model the volumetric deposition of any number of photon or ion spectra each incident at arbitrary angles. Convective and radiative boundary conditions are handled as well as the ability to impose any initial temperature profile. The heat diffusion equ… more
Date: January 3, 2005
Creator: Abbott, R P
Item Type: Refine your search to only Text
open access

Superconducting Combined Function Magnet System for J-PARC Neutrino Experiment.

Description: The J-PARC Neutrino Experiment, the construction of which starts in JFY 2004, will use a superconducting magnet system for its primary proton beam line. The system, which bends the 50 GeV 0.75 MW proton beam by about 80 degrees, consists of 28 superconducting combined function magnets. The magnets utilize single layer left/right asymmetric coils that generate a dipole field of 2.6 T and a quadrupole field of 18.6 T/m with the operation current of about 7.35 kA. The system also contains a few co… more
Date: October 3, 2004
Creator: Ogitsu, T.; Ajima, Y.; Anerella, M.; Escallier, J.; Ganetis, G.; Gupta, R. et al.
Item Type: Refine your search to only Article
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