An improved approximation algorithm for a scheduling problem with transporter coordination

We study the following scheduling problem with transportation. Given a set of n jobs that need to be processed on a single machine, we need to deliver the finished jobs to one of the two destinations using a single transporter. The goal is to minimize the time that all the jobs are delivered to their destination, such that the transporter returns. We propose a 11/6+ε -approximation algorithm which improves upon the best-known approximation ratio of 2.