Ten jobs are required to be processed on two machines M1 and M2 in the order 'M1 followed by M2'. Processing times are given here. Determine the optimal sequence(s) and evaluate for total elapsed time.

(a) Minimum time is 2 hours each for jobs J2 and J7 on machine M2. So rank J7 in the end, preceded by J2. Else, put J2 in the end, preceded by J7. Delete J2 and J7•

(b) From the remaining, minimum time is 3 hours for J4 on machine M1• So do J4 first.

(c) Now, the minimum time is 4 hours forjobJ1, on machineM2 and for jobJ6 on machineM1. Therefore, order J6 at the first and J 1 at the last available places.

(d) Having deleted jobs J4, J6, J1, J2 and J7, the minimum time is 5 hours on machine M1 in respect of the job J9• So order J9 immediately after J6•
(

e) In the jobs remaining, the least time is 6 hours for the job J 10 on machines M1 and M2 each, for job J3 on machine M2 and the job Jg on machine M2• Thus, rank J10 and Jg is the end preceded or, alternately, succeeded by job J3•

Transcribed Image Text:

Processing Time (hours) Job ... J J J4 J5 J6 Jy J8 10 Machine M : 7 8 10 3 7 4 5 8 5 6 Machine M2 : 4 2 6 6 5 7 2 6 7 6