On-Line Batchwise Workpiece Scheduling with Restriction of Time Interval

Studies the problem of on-line batchwise workpiece scheduling on m identical parallel machines of which the objective is to minimize the makespan,i.e.,the time for finishing the last workpiece in a batch. In such a case all the workpieces arrive in batches and each batch has exactly m workpieces to which the processing time required for each one depends on the time the batch containing it just arrives.It supposes that the processing time be restricted in a time interval.When a batch of workpieces arrives we shall schedule them immediately without interruption though no information is provided for subsequent batches.An on-line heuristic listing algorithm for batchwise workpieces scheduling is thus proposed according to LPT rule by which the workpieces in next batch will be scheduled immediately if all workpieces in a batch have already been scheduled.The worst case was analyzed with the competitive ratio given.