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Anchor Toolkit - a secure mobile agent system

Description: Mobile agent technology facilitates intelligent operation insoftware systems with less human interaction. Major challenge todeployment of mobile agents include secure transmission of agents andpreventing unauthorized access to resources between interacting systems,as either hosts, or agents, or both can act maliciously. The Anchortoolkit, designed by LBNL, handles the transmission and secure managementof mobile agents in a heterogeneous distributed computing environment. Itprovides users with t… more
Date: May 19, 1999
Creator: Mudumbai, Srilekha S.; Johnston, William & Essiari, Abdelilah
Partner: UNT Libraries Government Documents Department
open access

Hydrogen Release from Irradiated Vanadium Alloy V-4Cr-4Ti

Description: The present work is an attempt to obtain data concerning the influence of neutron and ? irradiation upon hydrogen retention in V-4Cr-4Ti vanadium alloy. The experiments on in-pile loading of vanadium alloy specimens at the neutron flux density 1014 n/cm2s, hydrogen pressure of 80 Pa, and temperatures of 563, 613, and 773 K were carried out using the IVG.1M reactor of the Kazakhstan National Nuclear Center. A preliminary set of loading/degassing experiments with non-irradiated material has been … more
Date: September 1, 1999
Creator: Klepikov, A. Kh.; Romanenko, O. G.; Chikhray, E. V.; Tazhibaeva, I. L.; Shestakov, V. P. & Longhurst, Glen Reed
Partner: UNT Libraries Government Documents Department
open access

Approaches to rid cathodic arc plasmas of macro- andnanoparticles: A review

Description: A major obstacle for the broad application of cathodic arc plasma deposition is the presence of micro- and nanoparticles in the plasma, also often referred to as 'macroparticles'. This paper reviews the formation of macroparticles at cathode spots, their interaction with the arc plasma and substrate, and macroparticle separation and removal from the plasma by various filtering methods. Nineteen variants of filters are discussed, including Aksenov's classic 90{sup o}-duct filter, filters of open… more
Date: June 1, 1999
Creator: Anders, Andre
Partner: UNT Libraries Government Documents Department
open access

Transformation as a Design Process and Runtime Architecture for High Integrity Software

Description: We have discussed two aspects of creating high integrity software that greatly benefit from the availability of transformation technology, which in this case is manifest by the requirement for a sophisticated backtracking parser. First, because of the potential for correctly manipulating programs via small changes, an automated non-procedural transformation system can be a valuable tool for constructing high assurance software. Second, modeling the processing of translating data into informatio… more
Date: April 5, 1999
Creator: Bespalko, Stephen J. & Winter, Victor L.
Partner: UNT Libraries Government Documents Department
open access

High-precision reflectometry of multilayer coatings for extreme ultraviolet lithography

Description: Synchrotron-based reflectometry is an important technique for the precise determination of optical properties of reflective multilayer coatings for Extreme Ultraviolet Lithography (EUVL). Multilayer coatings enable normal incidence reflectances of more than 65% in the wavelength range between 11 and 15 nm. In order to achieve high resolution and throughput of EUVL systems, stringent requirements not only apply to their mechanical and optical layout, but also apply to the optical properties of t… more
Date: December 29, 1999
Creator: Wedowski, M; Underwood, J H; Gullikson, E M; Bajt, S; Folta, J A; Kearney, P A et al.
Partner: UNT Libraries Government Documents Department
open access

Gold Beam Losses at the AGS Booster Injection.

Description: Gold beam injection efficiency decreases in proportional to the beam loss in the AGS Booster. A close look shows that large number of electrons, ions, and neutral particles are created when the gold beam scrapes wall. To investigate the neutral particle production due to the beam loss, local vacuum measurement was made during the 1998 run. It shows that the pressure created by the Booster Au{sup 31+} beam loss at injection has a 35 ms decay time constant. The beam loss created pressure bump in … more
Date: March 29, 1999
Creator: Zhang, S. Y. & Ahrens, L. A.
Partner: UNT Libraries Government Documents Department
open access

A Cupronickel Rotating Band Pion Production Target for Muon Colliders.

Description: A conceptual design is presented for a high power cupronickel pion production target. It forms a circular band in a horizontal plane with approximate dimensions of: 2.5 meters radius, 6 cm high and 0.6 cm thick. The target is continuously rotated at 3 m/s to carry heat away from the production region to a water cooling channel. Bunches of 16 GeV protons with total energies of 270 kl and repetition rates of 15 Hz are incident tangentially to arc of the target along the symmetry axis of a 20 Tesl… more
Date: March 29, 1999
Creator: King, B. J.; Weggel, R. J.; Mokhov, N. V. & Moser, S. S.
Partner: UNT Libraries Government Documents Department
open access

Search for Squarks and Gluinos in Events Containing Jets and a Large Imbalance in Transverse Energy

Description: Using data corresponding to an integrated luminosity of 79 pb{sup -1}, D0 has searched for events containing multiple jets and large missing transverse energy in p{bar p} collisions at {radical}s = 1.8 TeV at the Fermilab Tevatron collider. Observing no significant excess beyond what is expected from the standard model, they set limits on the masses of squarks and gluinos and on the model parameters m{sub 0} and m{sub 1/2}, in the framework of the minimal low-energy supergravity models of super… more
Date: February 1, 1999
Creator: Abbott, B.; Abolins, M.; Abramov, V.; Acharya, B. S.; Adam, I.; Adams, D. L. et al.
Partner: UNT Libraries Government Documents Department
open access

Precision Magnetic Elements for the SNS Storage Ring.

Description: Magnetic elements for an accumulator storage ring for a 1 GeV Spallation Neutron Source (SNS) have been under design. The accumulation of very high intensity protons in a storage ring requires beam optical elements of very high purity to minimize higher order resonances in the presence of space charge. The parameters of the elements required by the accumulator lattice design have been reported. The dipoles have a 17cm gap and are 124cm long. The quadrupoles have a physical length to aperture di… more
Date: March 29, 1999
Creator: Danby, G.; Jackson, J. & Spataro, C.
Partner: UNT Libraries Government Documents Department
open access

A P-Carbon CNI Polarimeter for RHIC.

Description: The RHIC spin program requires excellent polarimetry so that the knowledge of the beam polarization does not limit the errors on the experimental measurements. However, polarimetry of proton beams with energies higher than about 30GeV poses a difficult challenge. For polarization monitoring during operation, a fast and reliable polarimeter is required that produces a polarization measurement with a 10% relative error within a few minutes. The p-Carbon elastic scattering in the Coulomb-Nuclear-S… more
Date: March 29, 1999
Creator: Huang, H.; Bai, M.; Bunce, G.; Makdisi, Y.; Roser, T.; Imai, K. et al.
Partner: UNT Libraries Government Documents Department
open access

Design of a Resonant Extraction System for the AGS Booster.

Description: The Booster Application Facility (BAF) will employ heavy ion beams of many different ion species and at beam energies ranging from 0.04 to 3.07 GeV/nucleon. Resonant extraction is required in order to deliver a continuous stream of particles. In this report we describe the beam requirements and the system design. The basic design is a third integer resonant extraction process which employs a single thin magnetic septum and a thick septum ejector magnet The expected extraction efficiency is abou… more
Date: March 29, 1999
Creator: Brown, K.; Cullen, J.; Glenn, J. W.; Lee, Y. Y.; Mcnerney, A.; Niederer, J. et al.
Partner: UNT Libraries Government Documents Department
open access

RHIC Beam Loss Monitor System Initial Operation.

Description: The RHIC Beam Loss Monitor (BLM) System is designed to prevent beam loss quenching of the superconducting magnets, and acquire loss data. Four hundred ion chambers are located around the rings to detect losses. The required 8-decade range in signal current is compressed using an RC pre- integrator ahead of a low current amplifier. A beam abort may be triggered if fast or slow losses exceed programmable threshold levels. A micro-controller based VME module sets references and gains and reads tri… more
Date: March 29, 1999
Creator: Witkover, R. L.; Michnoff, R. J. & Geller, J. M.
Partner: UNT Libraries Government Documents Department
open access

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

Description: 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 di… more
Date: September 20, 1999
Creator: CHASE,B. CITTERIO,M. LANNI,F. MAKOWIECKI,D. RADEKA,S. RESCIA,S. TAKAI,H. ET AL.
Partner: UNT Libraries Government Documents Department
open access

The Design of a Liquid Lithium Lens for a Muon Collider.

Description: The last stage of ionization cooling for the muon collider requires a multistage liquid lithium lens. This system uses a large ({approx}0.5 MA) pulsed current through liquid lithium to focus the beam while energy loss in the lithium removes momentum which will be replaced by linacs. The beam optics are designed to maximize the 6 dimensional transmission from one lens to the next while minimizing emittance growth. The mechanical design of the lithium vessel is constrained by a pressure pulse due… more
Date: March 29, 1999
Creator: Hassanein, A.; Norem, J.; Reed, C.; Palmer, R. B.; Silvestrov, G.; Vsevolozhskaya, T. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Beam Instrumentation for the Spallation Neutron Source Ring.

Description: The Spallation Neutron Source (SNS) will be constructed by a multi-laboratory collaboration with BNL responsible for the transfer lines and ring. [1] The 1 MW beam power necessitates careful monitoring to minimize un-controlled loss. This high beam power will influence the design of the monitors in the high energy beam transport line (HEBT) from linac to ring, in the ring, and in the ring-to-target transfer line (RTBT). The ring instrumentation must cover a 3-decade range of beam intensity duri… more
Date: March 29, 1999
Creator: Witkover, R. L.; Cameron, P. R.; Shea, T. J.; Connolly, R. C. & Kesselman, M.
Partner: UNT Libraries Government Documents Department
open access

Generalized b-spline subdivision-surface wavelets and lossless compression

Description: We present a new construction of wavelets on arbitrary two-manifold topology for geometry compression. The constructed wavelets generalize symmetric tensor product wavelets with associated B-spline scaling functions to irregular polygonal base mesh domains. The wavelets and scaling functions are tensor products almost everywhere, except in the neighborhoods of some extraordinary points (points of valence unequal four) in the base mesh that defines the topology. The compression of arbitrary poly… more
Date: November 24, 1999
Creator: Bertram, M; Duchaineau, M A; Hamann, B & Joy, K I
Partner: UNT Libraries Government Documents Department
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