I appreciate the support of my staff in assembling the necessary information including M. Ilg, B. Lea, T. Springfield and J. Ilg. Dr. Z. Fang reviewed the manuscript and provided important suggestions. I am indebted to many of my colleagues for suggestions and past discussions that have been used here..

Lifetime Prediction, Roger W. Staehle, Adjunct Professor, Department of Chemical Engineering and Materials Science, University of Minnesota, Staehle Consulting Co.