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Displaying 43501 - 43525 of 74309

A Free-Boundary Model for Duffusion-Induced Grain Boundary Motion

January 1, 2002
Author(s)
P C. Fife, John W. Cahn, C M. Elliott
On the basis of a phase-field model previously proposed in Cahn et al. (acta Mater. 45, 4397-4413 (1997)) to describe the phenomenon of diffusion-induced grain boundary motion (DIGM), we present a formal asymptotic reduction to a moving free boundary

A High Speed Quantum Communication Testbed

January 1, 2002
Author(s)
Carl J. Williams, X Tang, M Hiekkero, J Rouzaud, R Lu, A Goedecke, Alan L. Migdall, A Mink, A Nakassis, Leticia S. Pibida, J Wen, Edward W. Hagley, Charles W. Clark

A Laser Tracker Calibration System

January 1, 2002
Author(s)
Daniel S. Sawyer, Bruce R. Borchardt, Steven D. Phillips, Charles Fronczek, William T. Estler
We describe a laser tracker calibration system developed for frameless coordinate metrology systems. The system employs a laser rail to provide an 'in situ' calibrated length standard that is used to test a tracker in several different configurations. The

A Lexical Analogy to Feature Matching and Pose Estimation

January 1, 2002
Author(s)
John A. Horst
We relate the problem of finding a correspondence between sensed and model features to that of finding a match between a random set of letters and words in a dictionary. The process is equivalent to hashing and the linguistic perspective is added to

A Novel Low Noise Regenerative Divide-by-Four Circuit

January 1, 2002
Author(s)
A G. Sen gupta, F L. Walls
We discuss a novel design of a self starting regenerative divider that permits division by 3, 4, 5, 6 ... instead of the usual 2. This is accomplished by having the loop oscillate simultaneously at two different frequencies, e. g., at f/4 and 3f/4. A

A Parallel 3D Dendritic Growth Simulator using the Phase-Field Method

January 1, 2002
Author(s)
William L. George, James A. Warren
We describe an implementation of a parallel finite-difference algorithm for the simulation of alloy solidification in three dimensions using the phase-field model. We also describe the visualization of the output from this simulator. Although thistype of

A Phase Diagram for the Bose-Einstein Condensation of Magnons

January 1, 2002
Author(s)
Lawrence H. Bennett, Edward Della Torre, Philip Johnson, R E. Watson
We have recently identified evidence of the Bose-Einstein condensation (BEC) of magnons in nanostructures. This behavior occurs for nanoparticles some 10s of nms in size (having some millions of atoms in a nanoparticle). Here we explore the effect of

A Phase-Field Model of Convection with Solidification

January 1, 2002
Author(s)
D M. Anderson, Geoffrey B. McFadden, A A. Wheeler
A phase-field model for the solidification of a pure material that incorporates convection has recently been developed. This model is a two-fluid model in which the solid phase is modeled as a sufficiently viscous fluid. The model allows for the solid and

A Weekly Cycle in Atmospheric Carbon Dioxide

January 1, 2002
Author(s)
R S. Cerveny, Kevin Coakley
We present a new statistic called the Mean Symmetrized Residual (MSR) for detection and quantification of a weekly cycle in measured daily atmospheric carbon dioxide (CO 2). At the Mauna Loa Observatory in Hawaii, we conclude that CO 2 concentrations, on
Displaying 43501 - 43525 of 74309