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Dr Stephen J. Maher



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Optimisation is an important part in all aspects of our world. The operation of railways, distribution of energy, scheduling of staff and routing of delivery vehicles are all examples of where optimisation is used significantly improve efficiency and effectiveness. The use of optimisation delivers a more productive and efficient world.

My research interests lie in the mathematics, algorithms and software that is applied to solve large scale optimisation problems. Of particular interest are optimisation problems that are too large to be solved by current general purpose techniques. Such problems include crew and aircraft scheduling for airlines and full planning of supply chain networks.

Our ability to solve such large scale problems typically relies on the application of decomposition techniques. I have experience in the application and implementation of the classical decomposition techniques of Benders' decompositon and Dantzig-Wolfe reformulation. I have successfully applied these decomposition techniques to optimisation problems arising from the airline and railway industries, location planning, transportation and the analysis of HIV.

I am a main developer of the fastest non-commercial mixed integer programming solver SCIP. In a recent project, I led the development of the Benders' decomposition framework for SCIP. I am a contributing developer for the general purpose column generation solver GCG.