Kim, Hee Joon and Kim, YoungHee (2011) A unified transformation function for lower and upper bounding constraints on model parameters in electrical and electromagnetic inversion. Journal of Geophysics and Engineering, 8 (1). pp. 21-26. ISSN 1742-2132 http://resolver.caltech.edu/CaltechAUTHORS:20110321-101139906
Full text not available from this repository.
Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20110321-101139906
Since many geophysical inverse problems are ill-posed, implementation of model parameter constraints is important in reducing solution ambiguity. This paper presents a unified transformation function for enforcing lower and upper bounds on model parameters to restrict model updates during the inversion process such that unrealistic results are suppressed. The transformation is realized using a logarithmic or inverse hyperbolic tangent function on model parameters, and contains the conventional transformations as special cases. It is straightforward to recast the cost functional gradient in terms of the transformed variable. The interval between lower and upper bounds reflects the reliability of a priori information, which may be obtained from well logging and surface geological surveys. Tests on a synthetic crosswell electromagnetic example reveal that the use of bound constraints is effective in deriving valid physical results from inversion.
|Additional Information:||© 2011 Nanjing Geophysical Research Institute. Received 3 July 2010; Accepted for publication 27 October 2010; Published 1 December 2010. This work was supported by the Korea Research Foundation grant (KRF-2008-013-D00159). We would like to thank two anonymous reviewers for their valuable comments in improving the quality of this manuscript.|
|Subject Keywords:||a priori information, constraint, inverse problems|
|Usage Policy:||No commercial reproduction, distribution, display or performance rights in this work are provided.|
|Deposited By:||Tony Diaz|
|Deposited On:||21 Mar 2011 20:24|
|Last Modified:||21 Mar 2011 20:24|
Repository Staff Only: item control page