This project was undertaken by Iain Walker and Elisabeth de Zwart as part of the requirements for their BCom (Hons) in Management Science/Operations Research.


SuperScheduler was developed to improve the supply chain efficiency of the American division of a global consumer goods company (the Company).


The Situation


The Company wishes to optimise the process of selecting a site to ship customer orders from. The shipping site is currently fixed, normally on the basis of closeness, but historical factors can impact this. Also, the exact product mix on a shipment, and availability of products and physical capacity at possible shipping sites mean that picking the closest plant is not necessarily a minimum cost strategy.


In the following example, a more distant shipping site makes a better choice due to product availability.




Implementation of integer program





The Solution Process


A Microsoft Access database was set up in a form that enabled easy updating as new information is received. It uses SQL queries to order the data in tables that are then in a form to be imported into the linear programming software, AMPL. A mixed-integer linear program was iteratively developed in AMPL and solved using CPLEX 8.0 to select the minimum-cost dispatch site, while still ensuring feasibility of the solution.


Relationship Diagram




Comparisons between the current strategy employed by the client and solving a model show that savings of up to 12% can be made, based on the provided test data (live data from 2 sites). This indicates that it would be worthwhile for the company to utilise an optimisation technique on its supply chain, with the potential to provide multi-million dollar savings annually.

This project enabled the generation of ideas that may aid in future analysis of the supply chain situation.




Iain and Lis would like to acknowledge the continued support of our supervisors, Dr. Shane Dye and Dr. Pavel Castka, and the other members of the Department of Management for their feedback.


Thanks also to Craig MacLeod, of Orbit Systems, for providing us with this project and assistance.


Finally, cheers to Brendon, Kingsley and Tom – the year wouldn’t have been the same without you guys!