1. Assistant Professor, Dept. of Mechanical and Industrial Engineering, IIT-Roorkee, Roorkee 247667, India. E-mail: singhfme@iitr.ernet.in
2. Professor, School of Engineering Sciences, Aeronautics and Astronautics, Univ. of Southampton, Southampton SO17 1BJ, U.K. E-mail: n.sandham@soton.ac.uk
3. Professor, Dept. of Engineering, Queen Mary, Univ. of London, Mile End Rd., London E1 4NS, U.K. E-mail: J.J.R.Williams@qmul.ac.uk