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Maximum likelihood techniques applied to quasi-elastic light scatteringThere is a necessity of having an automatic procedure for reliable estimation of the quality of the measurement of particle size from QELS (Quasi-Elastic Light Scattering). Getting the measurement itself, before any error estimates can be made, is a problem because it is obtained by a very indirect measurement of a signal derived from the motion of particles in the system and requires the solution of an inverse problem. The eigenvalue structure of the transform that generates the signal is such that an arbitrarily small amount of noise can obliterate parts of any practical inversion spectrum. This project uses the Maximum Likelihood Estimation (MLE) as a framework to generate a theory and a functioning set of software to oversee the measurement process and extract the particle size information, while at the same time providing error estimates for those measurements. The theory involved verifying a correct form of the covariance matrix for the noise on the measurement and then estimating particle size parameters using a modified histogram approach.
Document ID
19940012245
Acquisition Source
Legacy CDMS
Document Type
Contractor Report (CR)
Authors
Edwards, Robert V.
(Case Western Reserve Univ. Cleveland, OH, United States)
Date Acquired
September 6, 2013
Publication Date
August 24, 1992
Subject Category
Optics
Report/Patent Number
NAS 1.26:193550
NASA-CR-193550
Report Number: NAS 1.26:193550
Report Number: NASA-CR-193550
Accession Number
94N16718
Funding Number(s)
CONTRACT_GRANT: NCC3-115
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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