Workshop Queue System Modification Through Multi Priority Strategy

Abstract

This research focused on the modification of a queuing system in a workshop practice that repairs crankshafts using multi priority strategy. The random distribution of the inter arrival time of the crankshafts as well as the service time were statistically determined using Chi square goodness of fit test. The results obtained show that all the classes conform to Poisson distribution. For the non-preemptive priority, the mean waiting time in queue results for the first, second and third classes are 0.066, 0.09 and 0.224 day, respectively, while for the preemptive priority the three classes show 0.007, 0.036 and 0.258. Besides, the mean waiting time in queue for no priority system is 0.17 day. Arrivals that are of higher priority classes in preemptive priority systems enjoy huge improvement when compared with non-preemptive system. On the other hand, the improvement gained in higher priority classes has detrimental effect on the low priority class. Similar scenario plays out when the results of the mean waiting time in the system was analyzed. It is therefore advocated that priority strategy should be adopted for a system that may have urgent or semi-urgent jobs among the pool of jobs that needs repair to avoid possible losses arising from frequent reneging or balking of such jobs.