1. Department of Production Engineering, KTH Royal Institute of Technology, Brinellvägen 68, Stockholm 100 44, Sweden e-mail:
2. School of Engineering Science, University of Skövde, P.O. Box 408, Skövde SE-541 28, Sweden e-mail:
3. Fellow ASME Department of Production Engineering, KTH Royal Institute of Technology, Brinellvägen 68, Stockholm 100 44, Sweden e-mail: