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 B | 26 | 89 | 5 | 14 |
| Component D | 35 | 112 | 2 | 15 |
| Component A | 24 | 55 | 3 | 17 |
| Component C | 57 | 96 | 4 | 18 |
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 A → Component B → Component C → Component D
2. Calculate completion times and penalties:
- Component A: completes at 24, due 55, early by 31 min → penalty 93
- Component B: completes at 50, due 89, early by 39 min → penalty 195
- Component C: completes at 107, due 96, late by 11 min → penalty 198
- Component D: completes at 142, due 112, late by 30 min → penalty 450
3. Total penalty: 936
Answer: 936 penalty points
Key Strategy: JIT scheduling minimizes total earliness + tardiness penalties, balancing inventory costs and customer satisfaction.
1. EDD Sequence: Component A → Component B → Component C → Component D
2. Calculate completion times and penalties:
- Component A: completes at 24, due 55, early by 31 min → penalty 93
- Component B: completes at 50, due 89, early by 39 min → penalty 195
- Component C: completes at 107, due 96, late by 11 min → penalty 198
- Component D: completes at 142, due 112, late by 30 min → penalty 450
3. Total penalty: 936
Answer: 936 penalty points
Key Strategy: JIT scheduling minimizes total earliness + tardiness penalties, balancing inventory costs and customer satisfaction.