1. Dept. of Mechanical Engineering, Univ. of Canterbury, Christchurch 8140, New Zealand.
2. Senior Lecturer, Dept. of Mechanical Engineering, Univ. of Canterbury, Christchurch 8140, New Zealand (corresponding author).
3. Senior Lecturer, Dept. of Mechanical Engineering, Univ. of Canterbury, Christchurch 8140, New Zealand.
4. Distinguished Professor, Dept. of Mechanical Engineering, Univ. of Canterbury, Christchurch 8140, New Zealand.
5. Yoh Family Associate Professor, Dept. of Civil Engineering, Duke Univ., Durham, NC 27708-0287.
6. Research Engineer, Univ. of California, Los Angeles, CA 90095-1593.
7. Associate Professor, Dept. of Civil Engineering and Natural Resources, Univ. of Canterbury, Christchurch 8140, New Zealand.