This book is dedicated to the memory of Professor Zdzisaw Pawlak who passed away almost six year ago. He is the founder of the Polish school of Artificial Intelligence and one of the pioneers in Computer Engineering and Computer Science with worldwide influence. He was a truly great scientist, researcher, teacher and a human being.

This book prepared in two volumes contains more than 50 chapters. This demonstrates that the scientific approaches discovered by of Professor Zdzisaw Pawlak, especially the rough set approach as a tool for dealing with imperfect knowledge, are vivid...