We are saddened by the loss of Prof Lee Loo Hay who passed away on 17 March 2022 at the age of 53 after returning home from jogging.

Prof Lee started his research career as a PhD student at Harvard, studying under Prof Larry Yu-Chi Ho. After receiving his doctorate in 1997, he joined the then Department of Industrial and Systems Engineering (ISE) of NUS. For 25 years, he was a beloved and highly respected faculty member of the ISE Department and then the Department of Industrial Systems Engineering and Management (ISEM).

Prof Lee was an internationally recognised authority in the fields of simulation-based optimisation and maritime logistics and supply chain. At the time of his passing, he was the Director of the Centre of Maritime Studies, a university-level centre of NUS.

A Vibrant Leader in Container Port Operations Research

Prof Lee conducted highly impactful research in modern container port operations. He was known in his field for deriving efficient algorithms for managing ports and was a pioneer in proposing influential consignment strategies that are very effective in improving the productivity of transhipment ports. In 2013, he led an international team that won the USD 1 million grand prize of the Next Generation Container Port Challenge with a revolutionary double-story container terminal design concept entitled “SINGA Port (Sustainable Integrated Next Generation Advanced PORT)”.

In 2018, he and ISEM colleague Prof Chew Ek Peng found the Centre of Excellence in Modelling and Simulation for Next Generation Logistics (C4NGL) and the Centre of Excellence in Modelling and Simulation for Next Generation Ports (C4NGP), supported by external funding close to SGD 20 million. These centres have played a key role in developing technologies in line with the Singapore government’s initiatives in industry digitisation and developing a smart nation. He and his team made breakthroughs in the development of digital twin models to facilitate the design of the next generation automated container ports, integrating state-of-the-art simulation and optimisation technologies.

In the field of simulation-based optimisation methodologies, Prof Lee is a prolific developer of efficient multi-objective simulation optimisation approaches to solve problems encountered in manufacturing, transportation, logistics, and other automation systems. His approaches made novel breakthroughs, improving existing simulation efficiencies significantly. He was the Program Chair for the INFORMS Winter Simulation Conference (2022) to be held in Singapore.

Prof Lee always led by example to translate his research to create practical impact and value. For example, the multi-objective simulation optimisation algorithm he developed was incorporated in a proprietary software by DSimlab for their airline customers such as Airbus. He and his team developed an open-source platform, the Object-Oriented-Discrete-Event-Simulation (O2DES.Net), which is able to integrate simulation and optimisation seamlessly and has been used to build the digital twin for the Singapore mega port.

An Inspiring Educator and Mentor

Prof Lee was widely known to his students as a passionate, inspirational and energetic teacher, who truly cared for their well-being. He taught a wide range of subjects, including supply chain and logistics management, discrete-event simulation, and operations research. He received numerous teaching awards, including the 2018 Supply Chain Educator Award.

Many of Prof Lee’s students fondly recall his ceaselessly cheerful and optimistic attitude in life, and his always being available to provide encouragement and friendship. Every year, Prof Lee would organise and host gatherings for different cohorts of his past students at his home.

A Man of Service and Warmth with a Life Fully Lived

At work, Prof Lee was always ready to move out of his comfort zone to help and support others, even when his plate was full. His mantra of “can help, just help”, was truly humbling and selfless, especially in a work environment that is highly competitive and often stressful.  His positive attitude and sincerity never failed to impress even those who were only briefly acquainted with him. Prof Lee also displayed insurmountable resilience in the face of challenges and setbacks and is an inspiring role model to many junior colleagues. He led a very dynamic life and was always on the move, travelling around the world to connect with his international collaborators.

Prof Lee volunteered as police officer at the Neighbourhood Police Centre, contributing to public law enforcement and patrolling the streets at night. When asked why he would sacrifice precious sleep to do this, he remarked that doing so provided stress relief from his day job, and furthermore, helping others during his police duty was a reminder of how small his own problems were. He also said, being a policeman had been his childhood aspiration, and he believed that life is too short to not chase your dreams. He was also an avid cycling enthusiast, and enjoyed playing the guitar and singing for his church community.

Prof Lee is survived by his wife Flora and their two children Hannah and Jeremy.

Associate Professor Ng Szu Hui, Head of ISEM Department, said of Prof Lee’s passing, "We are honoured to have had Loo Hay as part of our ISEM family for the past 25 years.  Over this time, his contributions and achievements have been immense. Loo Hay has touched the lives of many colleagues and friends he had worked with, and the numerous students he had taught and mentored.  He was a pillar at ISEM and will be greatly missed and remembered by all of us."