Yard crane dispatching to minimize maximum tardiness of the jobs

Abstract

Maritime freight shipping is a key factor in the world’s freight industry. In 2012 alone, over 9 billion tons of cargo was moved via maritime transport. A key factor in this trade is the usage of containers or “containerization”, large weathered steel boxes that allow convenient and efficient storage of goods to be shipped.

The containers are stored in Yard Blocks at ports. The movement of each container at the Yard Blocks is known as “Jobs” are serviced by Yard Cranes. Like any other machines servicing a sequence of Jobs, there will be delays caused by set up and processing time. In busy ports like the ports of Singapore which moved 532,176 kilotons of containers in total in the year of 2011 alone, time is of the essence. Time saved allows more jobs to be completed at a higher rate thus a faster turnaround for vessels docked here while time lost through needless delays and setups will cost a chain of lost. Therefore efficient and quick optimisation is a must.

Based on the paper “Adapting ACTRSS Rule to Yard Crane Dispatching to minimize Job Tardiness in Container Terminals” by Huang and Li(2013) they have successfully optimised the job window of a YC using ACTRSS Rule by reducing Total Weighted Tardiness. What this project seeks to accomplish is to instead sequence the jobs based on the principle of minimising Maximum Weighted Tardiness of the job window instead.

Evaluation of results indicates that though successful, the additional factors introduced could be further improved Suggestions of possible such improvements are given at the last section of the report.