Abstract:
Simulation of waiting lines has become a widely studied research area of many researchers.
Supermarket waiting lines are foremost among those experienced daily by ordinary Sri Lankans.
Waiting in queues wastes the time and it creates a bad reputation for any organization. The study
analyzed the performance of a supermarket and presented relative measures and recommendations
for improvements. The system was modeled using the student version of Rockwell ARENA 14.5.
Data were collected through direct observations for three hours in one Saturday. The sample
consisted of 100 observations for inter arrival times and service times at counters. Heavy crowd at
the supermarket permitted the study to analyze only three counters. ARENA Input Analyzer
recorded the probability distributions for each process. The model was run for a replication length
of three hours. The performance of the existing system was measured by the number of customers
served among the number arrived. This was recorded as 76.36 %. But the results showed higher
customer waiting times in queues. Thus the authors decided to increase the resources used at each
counter as a means of reducing the waiting time. The proposed model recorded the maximum
performance with lower waiting times as expected. Accordingly the authors recommended
employing two people at each counter to speed up the billing process. Further the layout of the
supermarket could be rearranged allowing adequate space for the customers to walk around.
