The author is grateful to ISTE Ltd., London, UK, for accepting to publish the book, in collaboration with John Wiley & Sons Inc., USA. She expresses her appreciation to the publishing team, for their professionalism and excellent production practices, while bringing out this book in three volumes.

The author expresses her sincere thanks to the Management and Principal, PSG College of Technology, Coimbatore, India for the support extended while writing the book.

The author would like to place on record her immense admiration and affection for her father, Late Professor G. A. Krishna Pai and her mother Rohini Krishna Pai for their unbounded encouragement and support to help her follow her life lessons and her sisters Dr. Rekha Pai and Udaya Pai, for their unstinted, anywhere-anytimeanything kind of help and support, all of which were instrumental and inspirational in helping this author create this work.