CityLines: Designing Hybrid Hub-and-Spoke Transit System with Urban Big Data

Abstract:

Rapid urbanization has posed significant burden on urban transportation infrastructures. In today’s cities, both private and public transits have clear limitations to fulfill passengers’ needs for quality of experience (QoE): Public transits operate along fixed routes with long wait time and total transit time; Private transits, such as taxis, private shuttles and ride-hailing services, provide point-to-point transits with high trip fare. In this paper, we propose CityLines, a transformative urban transit system, employing hybrid hub-and-spoke transit model with shared shuttles. Analogous to Airlines services, the proposed CityLines system routes urban trips a spokes through a few hubs or direct paths, with travel time as short as private transits and fare as low as public transits. CityLines allows both point-to-point connection to improve the passenger QoE, and hub-and-spoke connection to reduce the system operation cost. To evaluate the performance of CityLines, we conduct extensive data-driven experiments using one-month real-world trip demand data (from taxis, buses and subway trains) collected from Shenzhen, China. The results demonstrate that CityLines reduces 12.5%-44% average travel time, and aggregates 8.5%-32.6% more trips with ride-sharing over other implementation baselines.

Existing System:

To the best of our knowledge, we are the first to investigate hybrid hub-and-spoke transit model in solving urban transit planning problem. We discuss two closely related topics to our work: (1)urban computing and (2) hub-and-spoke network planning.

Urban computing integrates urban sensing, data management and data analytic together as a unified process to explore, analyze and solve existing critical problems in urban area such as traffic congestion, energy consumption and pollution.

Hub-and-spoke network planning has been extensively studied in the literature, where all trip demands need to be detoured via hubs to their destination spokes all attempt to address a single allocation hub-and-spoke problem, where multiple hubs are deployed, but all trips from the same spoke have to detour at the same hub. Develop solutions to multiple allocation hub-and-spoke problem, where trips from the same spoke, with different destination can potentially employ different hubs for detour.

Proposed System:

We propose CityLines, a transformative urban transit system, employing hybrid hub-and-spoke transit model with shared shuttles. Analogous to Airlines services, the proposed CityLines system routes urban trips a spokes through a few hubs or direct paths, with travel time as short as private transits and fare as low as public transits. CityLines allows both point-to-point connection to improve the passenger QoE, and hub-and-spoke connection to reduce the system operation cost. To evaluate the performance of CityLines, we conduct extensive data-driven experiments using one-month real-world trip demand data (from taxis, buses and subway trains) collected from Shenzhen, China. The results demonstrate that CityLines reduces 12.5%-44% average travel time, and aggregates 8.5%-32.6% more trips with ride-sharing over other implementation baselines.

 

Conclusion:

We make the first attempt to develop CityLines system for urban scale transportation services, that employs a hybrid hub-and-spoke transit model. The model allows both point-topoint connection to improve the passenger quality of experience, and hub-and-spoke connection to reduce the system operation cost. CityLines employs a two-step optimization framework to enable a scalable solution to the optimal hybrid hub-and-spoke planning problem. Comparing with other implementation baselines, the evaluation results (obtained with real world transit data) demonstrate that CityLines reduces 12.5%-44% average travel time, and aggregates 8.5%-32.6% more trips with ride-sharing.

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