**Acknowledgements**

This book has been made possible through the effective collaborations of all the enthusiastic chapter author contributors, who have the expertise and experience in various disciplines in the engineering of complex system. They deserve the sincerest gratitude for the motivation of creating such a book, for the encouragement in completing the book, for the scientific and professional attitude in constructing each of the chapters of the book, and for the continuous efforts toward improving the quality of the book. Without the collaboration and consistent efforts of the chapter contributors including authors and anonymous reviewers, the completion of this book would have not been possible. It has been gratifying to work with the staff of MDPI publisher through the development of this book. The assistance provided by the staff members has been valuable and efficient. I thank MDPI publisher specially Ms. Kristy Zhang and Ms. Vivian Lu for their production of a stylish book. Finally, the greatest thanks to Professor Reza N. Jazar and Mr. Bryn Crawford for their support and useful discussions.

Hamid Khayyam
