Paper presented at the 29th Annual Southern African Transport Conference 16 - 19 August 2010 "Walk Together", CSIR International Convention Centre, Pretoria, South Africa.This paper was transferred from the original CD ROM created for this conference. The material was published using Adobe Acrobat 8.0 Technology.
The original CD ROM was produced by Document Transformation Technologies Postal Address: PO Box 560 Irene 0062 South Africa. Tel.: +27 12 667 2074 Fax: +27 12 667 2766 E-mail: nigel@doctech URL: http://www.doctech.co.zaCD sponsored by TRANSNE
