WOUT VAN WEZEL, PHD, is Assistant Professor of Production System Design, Faculty of Management and Organization, University of Groningen, The Netherlands. His research interests include planning and scheduling, human-centered decision support systems, and production control. RENÉ J. JORNA, PHD, is Professor of Knowledge Management and Cognition, Faculty of Management and Organization, University of Groningen, The Netherlands. His research activities focus on knowledge representation, planning and scheduling, semiotics, knowledge management, and sustainable innovation. ALEXANDER M. MEYSTEL, PHD, is Professor in the College of Engineering, Drexel University. His research centers on intelligence control, autonomous robots, learning systems, computer architectures for cognitive machines, and manufacturing, as well as the theory of knowledge representation.