Using simulation model as a tool for analyzing bus service reliability and implementing improvement strategies

Seyed Mohammad Hossein Moosavi; Amiruddin Ismail; Choon Wah Yuen

doi:10.1371/journal.pone.0232799

Using simulation model as a tool for analyzing bus service reliability and implementing improvement strategies

PLoS One. 2020 May 7;15(5):e0232799. doi: 10.1371/journal.pone.0232799. eCollection 2020.

Authors

Seyed Mohammad Hossein Moosavi¹, Amiruddin Ismail², Choon Wah Yuen¹

Affiliations

¹ Faculty of Engineering, Centre for Transportation Research (CTR), University of Malaya (UM), Kuala Lumpur, Malaysia.
² Faculty of Engineering, Smart and Sustainable Township Research Centre, National university of Malaysia (UKM), Bandar Bangi, Malaysia.

Abstract

Bus services naturally tend to be unstable and are not always capable of adhering to schedules without control strategies. Therefore, bus users and bus service providers face travel time variation and irregularity. After a comprehensive review of the literature, a significant gap was recognized in the field of public transportation reliability. According to literature, there is no consistency in reliability definition and indicators. Companies have their own definition of bus service reliability, and they mostly neglect the passengers' perspective of reliability. Therefore, four reliability indicators were selected in this study to fill the gap in the literature and cover both passengers' and operators' perceptions of reliability: waiting time and on-board crowding level from passengers' perspective, and headway regularity index at stops (HRIS) and bus bunching/big gap percentage from operators' perspective. The primary objective of this research is to improve the reliability of high frequency of bus service and simulation tools currently being used by the public transportation companies. Therefore, a simulation model of bus service was developed to study the strategies to alleviate it. Four different types of strategies were selected and implemented according to Route U32 (Kuala Lumpur) specifications. Model out-put showed that control strategies such as headway-based dispatching could significantly improve headway regularity by almost 62% and the waiting time by 51% on average. Both holding strategies at key stops (previous and Prefol holding) have shown an almost similar impact on reliability indicators. Waiting time was reduced by 44% and 43% after the previous and Prefol Headway strategies were adopted, respectively. However, the implementation of the component of headway-based strategies at the terminal and key stops showed the best impact on reliability, in terms of passenger waiting time. Waiting time and excess waiting time were both significantly reduced by 52.86% and 81.44%, respectively. Nevertheless, the strategies did not show any significant positive effect on the level of crowding during morning peak hours.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Algorithms
Computer Simulation
Crowding
Humans
Motor Vehicles
Transportation*
Travel

Grants and funding

The authors would like to acknowledge the Centre for Transportation Research and Institute of Research Management and Services University of Malaya for providing research facilities and funding under the research grant IIRG009A-19SAH. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.