Question 1
A JIT manufacturing system has 4 jobs with the following data:
| Job | Processing (min) | Due Date (min) | Early Penalty/min | Late Penalty/min |
|-----|-----------------|----------------|-------------------|------------------|
| Component D | 38 | 83 | 3 | 10 |
| Component A | 23 | 77 | 1 | 16 |
| Component B | 59 | 121 | 5 | 20 |
| Component C | 31 | 66 | 3 | 14 |
Using the Earliest Due Date (EDD) sequencing rule, what is the total penalty incurred?
Step-by-step solution (JIT Penalty Calculation):
1. EDD Sequence: Component C → Component A → Component D → Component B
2. Calculate completion times and penalties:
- Component C: completes at 31, due 66, early by 35 min → penalty 105
- Component A: completes at 54, due 77, early by 23 min → penalty 23
- Component D: completes at 92, due 83, late by 9 min → penalty 90
- Component B: completes at 151, due 121, late by 30 min → penalty 600
3. Total penalty: 818
Answer: 818 penalty points
Key Strategy: JIT scheduling minimizes total earliness + tardiness penalties, balancing inventory costs and customer satisfaction.
1. EDD Sequence: Component C → Component A → Component D → Component B
2. Calculate completion times and penalties:
- Component C: completes at 31, due 66, early by 35 min → penalty 105
- Component A: completes at 54, due 77, early by 23 min → penalty 23
- Component D: completes at 92, due 83, late by 9 min → penalty 90
- Component B: completes at 151, due 121, late by 30 min → penalty 600
3. Total penalty: 818
Answer: 818 penalty points
Key Strategy: JIT scheduling minimizes total earliness + tardiness penalties, balancing inventory costs and customer satisfaction.