| 1966-1969 | Imperial College, London | Reseach Assistant | Developed software for computer-aided design and computer graphics, including programs to evaluate the illumination of buildings by daylight, and to display pictures with hidden-line removal. |
| 1970-1972 | British Airways | Senior Programmer | Implemented real-time scheduling software for a Flight Information system (FICO). |
| 1973-1984 | Computer Sciences of Australia | Senior Member of Consulting Staff | Worked on the AMP Society's AMPNET I and AMPNET II systems, which allowed AMP branches to access the corporate insurance database. Implemented enhancements to the RACF security system on MVS mainframes. |
| 1985-1987 | Cincom Systems of Australia | Lead Software Engineer | Designed and implemented the interface between the Vax MANTIS 4GL system and the ULTRA database management system. Helped develop a new version of the ULTRA DBMS written in C. |
| 1988-1989 | Free lance | Software Developer | On the Macintosh, developed prize-winning data compression software, and an application to produce decorative borders with various types of symmetry. |
| 1990 | Integrated Arts | Analyst/Programmer | Developed software for the Artisan DVE, a product whch produced Digital Video Effects by digital processing of video signals. |
| 1991-2007 | First Data | Lead Software Engineer | Worked on First Data's EFT system, which acquires financial transactions from a national network of ATMs and EFTPOS terminals, and switches them to card issuing institutions. The switch system performs numerous checks on each transaction, including verification of the cardholder's PIN. On the legacy Mercury switch system, he was responsible for improving the efficiency of overnight batch reporting runs, and upgrading the firmware of a cryptographic processing unit. On the new GalaxyEFT switch system, he was responsible for system security, and represented First Data on industry groups such as the APCA Technical Security Working Group, and the Standards Australia IT/5/4 sub-committee. |
"A New Approach to the Hidden Line Problem, Computer Journal, Vol. 14, pp 232-237, 1971.
"An Efficient Coding System for Long Source Sequences", IEEE Transactions on Information Theory, Vol. IT-27, No. 3, pp 280-291, May 1981.
"A Significance Rule for Multiple-Precision Arithmetic", ACM Transactions on Mathematical Software, March 1984.
"Periodic Tilings with Vertices of Species Number 3", Structural Topology, No. 20, 1993.