SANDIA REPORT SAND2007-6645 Unlimited Release Printed October 2007 Merging Spatially Variant Physical Process Models Under an Optimized Systems Dynamics Framework Thomas S. Lowry Suzanne A. Pierce Vincent C. Tidwell William O. Cain Prepared by Sandia National Laboratories Albuquerque, New Mexico 87185 and Livermore, California 94550 Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockhead Martin Company, for the United States Department of Energy’s National Nuclear Security Administration under Contract DE-AC04-94-AL85000. Approved for public release; further dissemination unlimited.