Minimizing flowtime and maximum earliness on a single machine

We consider the bicriteria scheduling problem of minimizing flowtime and maximum earliness on a single machine. The problem is known to be NP-hard. We develop heuristic procedures for generating all efficient sequences for the cases where machine idle time is either allowed or not allowed. For both cases we also discuss an algorithm that finds the best of the approximately efficient sequences for a given objective function by generating only a small subset of those sequences. We present computational results which demonstrate that the heuristic procedures and the algorithms perform very well.