Scheduling UET, UCT dags with release dates and deadlines

The problem of scheduling precedence graphs for which every task has to be executed in a non-uniform interval is considered, with interprocessor communication delays. For the following classes of graphs we will present a polynomial time algorithm that nds minimumlateness schedules. 1. Outforests on two processors. 2. Series-parallel graphs and opposing forests with the least urgent parent property (to be de ned) on two processors. 3. Inforests with the least urgent parent property on m processors.