Abstract：
:A computationally efficient pseudodynamical filtering setup is established for elasticity imaging (i.e., reconstruction of shear modulus distribution) in soft-tissue organs given statically recorded and partially measured displacement data. Unlike a regularized quasi-Newton method (QNM) that needs inversion of ill-conditioned matrices, the authors explore pseudodynamic extended and ensemble Kalman filters (PD-EKF and PD-EnKF) that use a parsimonious representation of states and bypass explicit regularization by recursion over pseudotime. Numerical experiments with QNM and the two filters suggest that the PD-EnKF is the most robust performer as it exhibits no sensitivity to process noise covariance and yields good reconstruction even with small ensemble sizes.
journal_name
Med Physjournal_title
Medical physicsauthors
Banerjee B,Roy D,Vasu RMdoi
10.1118/1.3158808subject
Has Abstractpub_date
2009-08-01 00:00:00pages
3470-6issue
8eissn
0094-2405issn
2473-4209journal_volume
36pub_type
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