1

JOB-SHOP SCHEDULING PROBLEM

Consider the following job-shop problem: Job Processing time (days) Due date (dayth)

A 3

B 2

C 5

D 8

E 1

F 6

G 4

H 3

5

10

15

17

13

18

12

30

Objective 1: to minimize total number of delays. Objective 2: to minimize total number of late jobs/tardiness Solve the problem to achieve each of the objective above using heuristic technique that is based on: i. Earliest due date ii. Shortest processing time iii. Longest processing time

2

Exercise: Consider the following job-shop problem: Job

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

Processing 4 time(days) Due date 8 (days) Penalty 3 cost (RM)

3

6

3

7

2

5

5

4

8

5

5

3

4

4

4

6

7

5

10 12

9

19 17 25 14 38 23 27 30 30 52 48 60 33 35 41

4

8

4

9

6

2

5

5

4

7

1

2

2

5

4

6

5

4

Objective 1: to minimize total number of delays. Objective 2: to minimize total number of late jobs Solve the problem to achieve each of the objective above using heuristic technique that is based on Earliest due date, Shortest processing time, and Longest processing time

3

Exercise: Consider the job-shop problem below: Job Processing time (days) Due date (day-th)

A

B

C

D

E

F

G

H

I

J

K

L

7

3

5

4

2

6

4

9

8

5

7

8

27

32

18

21

68

57

40

41

42

33

15

19

Schedule the sequence of the jobs to be processed to make sure that the total tardiness (total late job) is minimized using the Earliest due date, Shortest processing time, and Longest processing time.