Adaptive and stochastic algorithms for piecewise constant EIT and DC resistivity problems with many measurements

48 mins 38 secs,  674.62 MB,  MPEG-4 Video  640x360,  29.97 fps,  44100 Hz,  1.84 Mbits/sec
Share this media item:
Embed this media item:


About this item
Image inherited from collection
Description: Asher, U (University of British Columbia)
Tuesday 23 August 2011, 11:45-12:30
 
Created: 2011-08-30 15:49
Collection: Inverse Problems
Publisher: Isaac Newton Institute
Copyright: Asher, U
Language: eng (English)
Distribution: World     (downloadable)
Credits:
Author:  Asher, U
Director:  Steve Greenham
Explicit content: No
Aspect Ratio: 16:9
Screencast: No
Bumper: UCS Default
Trailer: UCS Default
 
Abstract: We develop fast numerical methods for the practical solution of the famous EIT and DC-resistivity problems in the presence of discontinuities and potentially many experiments or data.

Based on a Gauss-Newton (GN) approach coupled with preconditioned conjugate gradient (PCG) iterations, we propose two algorithms. One determines adaptively the number of inner PCG iterations required to stably and effectively carry out each GN iteration. The other algorithm, useful especially in the presence of many experiments, employs a randomly chosen subset of experiments at each GN iteration that is controlled using a cross validation approach. Numerical examples demonstrate the efficacy of our algorithms.
Available Formats
Format Quality Bitrate Size
MPEG-4 Video * 640x360    1.84 Mbits/sec 674.62 MB View Download
WebM 640x360    915.38 kbits/sec 325.72 MB View Download
Flash Video 484x272    568.82 kbits/sec 202.62 MB View Download
iPod Video 480x270    506.32 kbits/sec 180.35 MB View Download
MP3 44100 Hz 125.03 kbits/sec 44.34 MB Listen Download
Auto (Allows browser to choose a format it supports)