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Title: Fast singular value decomposition combined maximum entropy method for plasma tomography

Abstract

The maximum entropy method (MEM) is a widely used reconstruction algorithm in plasma physics. Drawbacks of the conventional MEM are its heavy time-consuming process and possible generation of noisy reconstruction results. In this article, a modified maximum entropy algorithm is described which speeds up the calculation and shows better noise handling capability. Similar to the rapid minimum Fisher information method, the modified maximum entropy algorithm uses simple matrix operations instead of treating a fully nonlinear problem. The preprocess for rapid tomographic calculation is based on the vector operations and the singular value decomposition (SVD). The initial guess of the sought-for emissivity is calculated by SVD and this helped reconstruction about ten times faster than the conventional MEM. Therefore, the developed fast MEM can be used for intershot tomographic analyses of fusion plasmas.

Authors:
;  [1]
  1. Department of Physics, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701(Korea, Republic of)
Publication Date:
OSTI Identifier:
20778741
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 77; Journal Issue: 2; Other Information: DOI: 10.1063/1.2169489; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ALGORITHMS; DECOMPOSITION; ELECTROMECHANICS; EMISSIVITY; ENTROPY; IMAGE PROCESSING; MICROSTRUCTURE; NONLINEAR PROBLEMS; PLASMA; PLASMA DIAGNOSTICS; TOMOGRAPHY

Citation Formats

Kim, Junghee, and Choe, W. Fast singular value decomposition combined maximum entropy method for plasma tomography. United States: N. p., 2006. Web. doi:10.1063/1.2169489.
Kim, Junghee, & Choe, W. Fast singular value decomposition combined maximum entropy method for plasma tomography. United States. doi:10.1063/1.2169489.
Kim, Junghee, and Choe, W. Wed . "Fast singular value decomposition combined maximum entropy method for plasma tomography". United States. doi:10.1063/1.2169489.
@article{osti_20778741,
title = {Fast singular value decomposition combined maximum entropy method for plasma tomography},
author = {Kim, Junghee and Choe, W.},
abstractNote = {The maximum entropy method (MEM) is a widely used reconstruction algorithm in plasma physics. Drawbacks of the conventional MEM are its heavy time-consuming process and possible generation of noisy reconstruction results. In this article, a modified maximum entropy algorithm is described which speeds up the calculation and shows better noise handling capability. Similar to the rapid minimum Fisher information method, the modified maximum entropy algorithm uses simple matrix operations instead of treating a fully nonlinear problem. The preprocess for rapid tomographic calculation is based on the vector operations and the singular value decomposition (SVD). The initial guess of the sought-for emissivity is calculated by SVD and this helped reconstruction about ten times faster than the conventional MEM. Therefore, the developed fast MEM can be used for intershot tomographic analyses of fusion plasmas.},
doi = {10.1063/1.2169489},
journal = {Review of Scientific Instruments},
number = 2,
volume = 77,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}
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