Exploring Operational Excellence: The Beale Lecture 2024

To celebrate 75 years of advancing operational research and fostering innovation, The OR Society proudly hosted one of its special flagship annual events – The Beale Lecture, on 8 February.

Honouring Martin Beale's Vision

This annual talk pays tribute to the visionary Martin Beale, renowned for his pioneering contributions to applied mathematics and statistical analysis. This year, our president Gilbert Owusu had the privilege of welcoming Professor Chris Potts, a distinguished figure in operational research, to deliver the keynote lecture entitled, ‘Reflections on Half a Century of Research in OR.’

Professor Chris Potts: A Career of Innovation

Gilbert explained that Professor Potts' illustrious career, spanning from his formative years at the University of Manchester to

his tenure as an Professor at the University of Southampton, has been marked by groundbreaking research in production scheduling, logistics, transport, healthcare and sports.

With over 100 published papers in prestigious journals, he has been an active promoter of operational research, serving on various committees of The OR Society, including as the Chair of the Southern OR Group. Additionally, he held the position of Vice- President of EURO (the Association of European OR Societies) from 2003 to 2006. He also played a pivotal role in the creation of NATCOR (National Taught Course Centre for Operational Research), providing training for doctoral students since

2008, and has conducted NATCOR courses in Combinatorial Optimisation at the University of Southampton on several occasions.

Nurturing future leaders

In addition, the Beale Lecture also focuses on nurturing the next generation of operational research leaders and we were thrilled to welcome Dr Spyridon Pougkakiotis, who won our esteemed Doctoral Award in 2022. Currently a lecturer in mathematics

at the University of Dundee, Dr Pougkakiotis discussed his PhD research in a presentation entitled, "A Regularised Interior Point Method for Convex Programming," shedding light on the intricacies of optimisation and computational mathematics.

A Regularised Interior Point Method for Convex Programming

Tackling complex mathematical problems efficiently is essential across many fields. One method often used is Interior Point Methods (IPMs). These techniques are known for providing accurate solutions quickly. However, they can struggle with inaccurate numbers in tricky mathematical scenarios. Dr Pougkakiotis explored how to create robust, efficient and scalable interior point methods.

Spyridon Pougkakiotis

He explained that to make IPMs better suited for real-world challenges, researchers have been exploring modified versions. These versions have shown improvement in stability during practical use, but until recently, there has not been a full understanding of how they work theoretically.

Dr Pougkakiotis introduced the IP-PMM method, a blend of an infeasible IPM and something called the Proximal Method of Multipliers (PMM). He explained that this combination creates a more dependable version of IPMs, especially for specific kinds of mathematical problems. He discussed how it works: the method uses IPMs for smaller math sub-problems within the PMM. It solves each sub-problem, then makes adjustments, forms new problems and repeats the process until it finds a satisfactory solution.

He said the exciting thing about this method is that it does not take too much time to work through a wide range of problems which is particularly important in maths research. By combining the speed of IPMs and the stability of PMMs, the IP-PMM method offers a promising and efficient solution.

He then discussed general strategies for efficiently solving related mathematical problems within the IP-PMM framework. He also showed numerical results across various mathematical problems to highlight the benefits of these IPM modifications and confirming the reliability and efficiency of the IP-PMM algorithm.

Reflecting on a half century of OR research

Professor Potts's lecture took us on a journey through his remarkable career, from his BSc in Mathematics at the University of Manchester to his PhD at the University of Birmingham, focusing on designing algorithms for machine-based scheduling problems. His work in scheduling continued during his tenure

as Lecturer in Mathematics at the University of Keele from 1973 to 1985, where he made significant advances in combinatorial optimisation to provide novel approaches for analysing and solving scheduling problems.

In 1985, he was appointed as Lecturer and later Professor, in Operational Research at the University of Southampton, broadening his research interests to including scheduling

research applied in new areas including sport (cricket, football, Formula One, and golf), logistics, transport (air, rail, and road) and healthcare. Although he retired in 2022, he has remained an Emeritus Professor ever since.

During his lecture, Professor Potts elaborated on the extensive breadth of his scheduling research, highlighting its pivotal role in addressing complex problems. His exploration ranged from designing branch and bound algorithms to heuristic design,

establishing performance bounds, determining the complexity of new scheduling problems and developing competitive algorithms for online scheduling. Furthermore, he delved into the design

and computational evaluation of metaheuristics for scheduling, illustrating how his research transcends theoretical frameworks to solve real-world challenges.

By providing tangible examples of scheduling problems, Professor Potts brought his research to life, highlighting its applicability in solving a myriad of problems, from machine scheduling to heuristic challenges. Through his comprehensive insights, he underscored the transformative potential of operational research in reshaping industries and driving innovation forward.

Transformative Applications in Sports

One of the highlights of the lecture was learning how Professor Potts worked with Neil Martin, an MSc student in OR in 1995, to apply his research in Formula One. The duo collaborated with McLaren to determine the best times to schedule pit stops for tyre changes and refuelling, thus optimising race strategy. This project involved key considerations around tyre wear, sector times and pit stop durations. The optimal laps for pit stops were determined using dynamic programming, resulting in enhanced race performance. Subsequently, Professor Potts and his team created a Formula One race simulator at the University of Southampton, funded by McLaren, further advancing research in the field.

Additionally, scheduling techniques were instrumental in the redesign of the FedEx Cup playoff series for the PGA Tour, initiated in 2007. Collaborating with Professor Nicholas G Hall, Professor Potts proposed an alternative design for the Tour Championship, introducing match play format to replace stroke play. This innovative approach addressed some of the previous complexities in points allocation and player selection, enriching the competitive dynamics of the tournament.

Professor Potts concluded by expressing his enduring enthusiasm for operational research and ongoing engagement in new projects. His impactful contributions exemplify the transformative potential of operational research in reshaping industries and driving innovation forward.

You can see and hear the presentations on The OR Society’s YouTube channel here: https://youtu.be/WvQjpvSvQXI