Sequencing n Jobs on Two Machines with Arbitrary Time Lags

Each of n jobs must be run first on machine I and then on machine I. Running times for each job on each machine are given. Also specified are arbitrary time lags which prescribe that a job may not be started completed on machine II until at least a certain time has elapsed since starting completing the job on machine I. A rule is given for determining the sequence in which jobs are to be run on the machines---using the same sequence for both machines---in order to minimize the time between the start of production of the first job on machine I and the completion of production of the last job on machine II.