Developing mathematical models and algorithms to improve efficiency of crane operations at sea ports

For more information and details on this technology, email research@iitbmonash.org

Major sea-ports and cargo terminals around the world routinely encounter the challenges of efficiently handling their cargo. At the port, containers are often stacked on the ground, one on top of the other till a ship or a train arrives that needs it. Ports typically handle hundreds of containers that are constantly picked-up, transported, stacked and re-stacked. Such operations depend critically on specialised cranes that are expensive in terms of capital expenditure as well as operational costs. Therefore, efficient planning, routing and scheduling of these cranes is critical for terminal throughput and efficacy. Through his research at IITB-Monash Research Academy, Niraj Ramesh Dayama is seeking to improve these aspects of crane scheduling at cargo terminals. Niraj chose this topic for his research after working in a large software company, which was commissioned to develop a system to provide efficient scheduling and planning solutions. The software sometimes took more than 250 hours to compute an efficient solutionfor moving up to only 100 containers; which gives an idea of the complexity of this problem. However, Niraj observed that experienced planners at ports often created quite efficient schedules -- relying upon rule-of-thumb techniques using just a pen and paper -- in a few minutes. Such low-technology experience based approachesactually proved to be more effective than expensive software programmes.

It wasn’t that the algorithms in the software programme were incorrect. Rather, they were not able to identify, capture and include the nuances of the problem structure. To the contrary, an experienced person, would rely upon established historical data and rule-of-thumb practices to generate efficient schedules quickly. Niraj saw this as an interesting challenge and set about to find a way to get quicker and more efficient schedules using better mathematical models and specialised algorithms. While there are many existing approaches and computer models to schedule container movement operations at ports, these have generally been ineffective when considering practical instances of such problems. Traditional approaches, including mixed-integer programming methods, would take approximately 5 to 6 days to solve practical instances of such a problem. Niraj’s models involve a decomposition of the practical sized instance into smaller, more manageable bits, and solving each of these individually. Niraj has found that his model works faster whilst also giving the best possible schedules. It is estimated in the future that Niraj’s system will be able to solve problem instances with over 100 containers and 5 cranes, within 20 minutes using a standard laptop. Another advancement that Niraj has made to increase the computational speed, is through the use of “greedy” depth first algorithms with back-tracking. Whilst exact algorithms provide the best solution, they can often be prohibitively time consuming.The greedy algorithms allow for a close (+/- 1%) solution in a much shorter time.

Reflecting on his time at the IITB-Monash Research Academy, Niraj comments “[the Academy] is giving something much bigger than a mere line in my resume and the word “Dr” in my title. Here, one gets a chance to interact with some of the brightest minds at two world-renowned institutions, to observe how these brilliant people approach various problems objectively and to learn several problem solving techniques. This PhD is more of a chance to question and redefine oneself in the process. This personal growth matters much more to me than the knowledge gained during the research itself.”

Graduate research scholars of IITB-Monash Research Academy study for a dually-badged PhD from both IIT Bombay and Monash University, spending time at both institutions to enrich their research experience. IITB-Monash Research Academy is a collaboration between India and Australia that endeavours to strengthen scientific relationships between the two countries.

Upon completing his PhD, Niraj will have provided a valuable resource not just to the shipping industry, but a generic tool which may have far reaching applications. It is expected that the model will be able to be utilised in other industries and applications that require sequence dependant scheduling, such as vehicle routing, machine scheduling, including industrial robot scheduling or even for courier companies. It is an exciting development that has the potential to transform the way businesses operate, making them more efficient and effective.

Research Scholar: Niraj Ramesh Dayama, IITB-Monash Research Academy

Project Title: Mathematical Models to Optimise Crane Operations At Cargo Container Trans-Shipment Terminals

Supervisors:Professor Narayan Rangaraj, Professor Vishnu Narayanan and Professor Mohan Krishnamoorthy

Contact Details: nirajdayama@gmail.com

Contact research@iitbmonash.org for more information on this, and other projects

The above story was written by Ms Rakhee Ghelani based on inputs from the research student and IITB-Monash Research Academy. Copyright IITB-Monash Research Academy.