Acknowledgments

The author expresses his deep gratitude to the members of the doctoral dissertation scientific advisory/supervising committee for their valuable comments and unfailing support on the forerunner of this work.

The author would also like to thank Mr. Panos Stogiannos for his assistance with the translation and editing of the manuscript. The author would also like to acknowledge the input and valuable contribution of Mr. Efthymios Kokmotos, PhD student in the Department of Production and Management Engineering of the Polytechnic School of Democritus University of Thrace, who read the manuscript and made insightful comments and suggestions.