Preface xv ACKNOWLEDGMENTS We thank the many individuals who have helped us in making this book a reality. First and foremost, we thank our editor Todd Green and Nancy Hoffmann for guid- ing us through the publication process and helping us meet our deadlines. We are also grateful for the technical input and editorial comments by current and former students, specifically C. Datsios, G. Keramidas, A. Papalambrou, and A. Voyiatzis. In addition, we thank the anonymous reviewers of book chapters, whose valuable comments enabled us to address and promote the appropriate technical concepts and to deliver a more readable book. Any failure to achieve these goals is, of course, the responsibility of the authors. Last, but definitely not least, we acknowl- edge the support and patience demonstrated by our families during the long process of developing this book. Without their understanding and extreme patience, this book would never have been completed.