Question

2. Determine the processing sequence for the six jobs shown below using Johnson's Rule. (A) Calculate total throughput (makespan) time. (12 pts) (B) Can the makespan be reduced by splitting the latest job? If so, by how much? (8 pts) Working Working Center 1 Center 2 Job 6 8 c 10 900 Resolution 20p HD-Ready Gateway FPD1975W TFTLCD Monitor Theft Detemce

Answer 1

(a) Using Johnson's algorithm,

First position will go to the job a which has shortest time with WS1

Last position will go to c which has shortest time with WS2

Second position from will go to d which has lowest time among the remaining tasks with WS1

Second last position will go to f which has lowest time with WS2 among the remaining tasks.

Third from last position will go to b which has least time with WS2.

Third position will be taken by the remaining activity, that is e.

The sequence is [ adebfc]

(b) Total makespan as shown in the chart is 54.

(c) If the last task (c) is split between WS1 and 2, in the duration of 7 and 8, with WSi and WS2 respectively will reduce the makespan by 3 days.