Optimal maintenance strategy for Technology-enhanced classrooms: a case study

The purpose of the study was to collect data and evaluate an age-based bulb replacement policy for projectors used in Technology-enhanced classrooms in a university campus. The Office of Information Technology (OIT) had instituted a policy to replace bulbs in these projectors after either failure or 1800 h of operation without failure. However, databases maintained by OIT included the time to bulb failure, the average number of times the bulbs were turned on and off per week, and the number of thermal events. Modeling the failure data with a Weibull proportional hazards model revealed that probability of bulb failure was a function of the number of hours a bulb was used and the frequency at which it was turned on and off. Combining this information with a cost model led to the recommendation for an improved condition-based replacement policy. Copyright © 2009 John Wiley & Sons, Ltd.