Zachariah Stevenson

Former MASc Student

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Operations or process scheduling is a problem whose relevance spans many different industrial and engineering fields such as mining, chemical production and manufacturing plants. The goal of process scheduling is to find an optimal schedule that can efficiently carry out operations at minimizing costs, in the shortest possible time (minimize turnaround time), or to maximize revenue. Following schedules that are tailored to meet the demands can greatly increase the overall efficiency of the operations or reduce overhead. There has been a great amount of research done in the field of process scheduling, both for theoretical purposes and the practical reasons mentioned above. However, the field still remains rich as more complex models made to more closely resemble real world conditions are considered. My research is focused around devising new methods and strategies for solving a real world scheduling problem at an analytical services facility. In practice with large facilities and moderately sized time horizons, finding optimal schedules is computationally expensive. The goal of my work is to find “good” quality solutions while keeping computational costs reasonable so that these strategies may be employed in practice. Since it is known that solving general integer programs (IPs) is NP-hard, I am not aiming to find algorithms that are necessarily theoretically efficient for solving the problem, I am interested in developing heuristics that perform well on the problem in practice.

Thesis: A computational study of practical issues arising in short-term scheduling of a multipurpose facility