[1] Department of Mechanical Engineering, University of Newcastle, Callaghan, Newcastle, NSW 2308, Australia
[2] Co-Oper. Res. Ctr. Adv. Compos. S., 506 Lorimer St., Fishermen's Bend, Vic. 3207, Australia
[3] Department of Physics, University of Newcastle, Callaghan, Newcastle, NSW 2308, Australia