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Displaying 47276 - 47300 of 74142

The TREC-8 Question Answering Track Report

December 11, 2000
Author(s)
Ellen M. Voorhees
The TREC-8 Question Answering track was the first large-scale evaluationof domain-independent question answering systems.This paper summarizes the results of the track by giving a briefoverview of the different approaches taken to solve the problem.The

Head Tracking Using Stereo

December 6, 2000
Author(s)
D Russakoff, Martin Herman
Head tracking is an important primitive for smart environments and perceptual user interfaces where the poses and movements of body parts need to be determined. Most previous solutions to this problem are based on intensity images and, as a result, suffer

A Phase-Field Model With Convection: Numerical Simulations

December 1, 2000
Author(s)
D M. Anderson, Geoffrey B. McFadden, A A. Wheeler
In a previously developed phase-field model of solidification that includes convection in the melt, the two phases are represented as viscous liquids, where the putative solid phase has a viscosity much larger than the liquid phase. In this paper we report

A Specification-Based Coverage Metric to Evaluate Test Sets

December 1, 2000
Author(s)
P E. Ammann, Paul E. Black
Software developers use a variety of methods, including both formal methods and testing, to argue that their systems are suitable components for high assurance applications. In this paper, we develop another connection between formal methods and testing by

Agent-Based Services for B2B Electronic Commerce

December 1, 2000
Author(s)
Elizabeth N. Fong, Nenad Ivezic, Thomas R. Rhodes, Y Peng
The potential of agent-based systems has not been realized yet, in part, because of the lack of understanding of how the agent technology supports industrial needs and emerging standards. The area of business-to-business electronic commerce (b2b e-commerce

Alpha Case Thickness Modeling in Investment Castings

December 1, 2000
Author(s)
William J. Boettinger, Maureen E. Williams, Sam R. Coriell, Ursula R. Kattner, B A. Mueller
The alpha case thickness at the surface of a Ti-6Al-4V step wedge investment casting has been measured and successfully predicted. The prediction uses temperature-time results obtained from a heat flow simulation of the casting that was performed with a

Asymmetric coupled CMOS lines-an experimental study

December 1, 2000
Author(s)
Uwe Arz, Dylan F. Williams, Dave K. Walker, Hartmut Grabinski
Abstract: This paper investigates the properties of asymmetric coupled lines built in a 0.25- m CMOS technology over the frequency range of 50 MHz to 26.5 GHz. We show that the frequency-dependent line parameters extracted from calibrated four-port

Chlorination in Combustion Systems

December 1, 2000
Author(s)
Wing Tsang, Valeri I. Babushok
This paper is concerned with the formation of polychorinated organics in the gas phase in combustion systems. The results are derived from simulation studies with inputs from the fundamental kinetics of single step thermal gas phase reactions. Attention is

Combinatorial Materials Science for Polymer Thin-Film Dewetting

December 1, 2000
Author(s)
J C. Meredith, A P. Smith, Alamgir Karim, Eric J. Amis
A combinatorial technique is described for rapid measurement of phenomena associated with thin-film polymer science. Thin-film libraries of polystyrene on silicon, containing systematic variations in film thickness and temperature, are prepared with a

Concrete Materials Database

December 1, 2000
Author(s)
C B. Oland, Chiara C. Ferraris
ACI Committee 126 on Database Formats for Concrete Materials Properties was organized in 1990 to develop and report information on database formats for concrete and related materials. The committee is accomplishing this mission by preparing guides for use

Control of Flow Direction in Microfluidic Devices with Polyelectrolyte Multilayers

December 1, 2000
Author(s)
S L. Barker, David J. Ross, Michael J. Tarlov, Michael Gaitan, Laurie E. Locascio
Electroosmotic flow (EOF) is commonly utilized in microfluidics. Because the direction of the EOF can be determined by the substrate surface charge, control of the surface chemical state offers the potential, in addition to voltage control, to direct the

Crystal Structure of the Monoclinic Perovskite Sr 3.94Ca d1.31^Bi 2.70 O 12

December 1, 2000
Author(s)
Winnie K. Wong-Ng, James A. Kaduk, Qingzhen Huang, Robert S. Roth
The crystal structure of the low temperature oxidized form of Sr 3.94Ca 1.31Bi 2.70O 12 has been determined using a combined Rietveld refinement technique with neutron, synchrotron, and powder x-ray diffraction data. The structure is pseudo-orthorhombic

Development of Arrays of TES X-ray Detectors

December 1, 2000
Author(s)
Steven Deiker, James A. Chervenak, Gene C. Hilton, Martin Huber, Kent D. Irwin, John M. Martinis, Sae Woo Nam, David A. Wollman
Both the x-ray astrophysics and microanalysis communities have a need for large format arrays of high-spectral-resolution x-ray detectors. To meet this need, we are transferring our successful single pixel Transition Edge Sensor (TES) x-ray

Directivity of the Test Device in EMC Measurements 1

December 1, 2000
Author(s)
Galen H. Koepke, David A. Hill, John M. Ladbury
We present a statistical theory for estimating the directive characteristics of unintentional emitters based on the electrical size of the device. We compare this theory to directivity derived from pattern measurements in an anechoic chamber. We also use

Editor's Preface

December 1, 2000
Author(s)
Kalman D. Migler, S G. Hatzikiriakos
The work of J.R. Rice has been central to developments in solid mechanics over the last thirty years. This volume collects 21 articles on deformation and fracture in honor of J.R. Rice on the occasion of his 60th birthday. Contributors include students (P
Displaying 47276 - 47300 of 74142
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