This preview shows page 1. Sign up to view the full content.
Unformatted text preview: on equipment records, the length of each run (in hours) was a random variable, T, where
T ~ N(21, 2). (5.7) With the amount of variation in the process, predicting the impact of different policies analytically
is difficult. Instead, analysis was performed using a simple discrete event modeling and simulation in
ProModel Silver. The framework and details are found in Appendix D. The results of the simulation
indicated that with current levels of process variation the MTSA machine could be run in a stable
manner at a minimum of four times a week. With this policy, however, average inventory increases
by about 7 cards (or 38%) and average cycle time increases by about 80 hours (or 39%). While the
increase in inventory was negligible in terms of required floor space (each card measures about one
square foot), the increase in cycle time required the changes to be made during a lull in customer
demand so as to avoid breaking short-term delivery commitments.
According to simulation and real-world experience, the policy change resulted in a negligible
increase in inventory cost due to increased floor space usage and holding costs. On the o...
View Full Document
- Spring '14