1. Associate, Conestoga-Rovers & Associates Ltd., 651 Colby Dr., Waterloo, ON N2V 1C2, Canada.
2. Professor, School of Engineering, Univ. of Guelph, Guelph, ON N1G 2W1, Canada
3. Professor, School of Engineering, Univ. of Guelph, Guelph, ON N1G 2W1, Canada (corresponding author).