Queue and waiting time in public transport management: Case study: Rwanda federation transport cooperative (RFTC)

Abstract

In Rwanda and particularly in Kigali, as time goes the demand for public transport increases with number of population and thus the travel demand growth is linked to the growth of population. According to the Census of 2012, only 7% of private households owned vehicles in City of Kigali (CoK) and this shows that the demand of public transport is at high level. On another hand, transport sector is one of the key engines of development, and hence improving the reliability of its infrastructure and quality of transport in general is major cornerstone to population lives. Some operations such as, payment means, capacity per bus, speed governor, road infrastructure, etc, have shown some improvement, but there is still a big room for improvement as well. Specifically in the way the service is offered to the passengers mostly on waiting time (time to be spent in queue, time needed to reach destination), number of passengers on queue utilizing a certain line at a given time. There is no visibility of the bus arrival time and headways, and these lead to uncertain fleet management performance. Furthermore, the mentioned challenges prevent both the Public Transport Service Providers (PTSP) and passengers to plan their trips in a proper way. In this work, various factors explain the reasons associated to the above issues in public transportation, and the relationship existing among them. Using the queue theory M/M/1 system, we developed an algorithm that optimizes the transport management system in Rwanda Federal of Transport Cooperative (RFTC) in Kigali whereby the optimum bus capacity, headways, and number of buses to allocate to a certain line is determined. We achieve the objectives by assessing existing data and means for buses’ allocation, assessing the number of passengers in queue, the arrival patterns, computing waiting time and related significances in system and in queue, and hence the proposal of new system that optimizes the service offered to Public Transport Services (PTS). The developed algorithm helps planning such as; Public Transport Service Providers (PTSP) to allocate efficiently resources and at same time to predict the bus arrival time, utilization rate and waiting time and thus improvement on the Quality of Service (QoS) offered to passengers.