Student Seminar by Ms. Luyun Zhao on Oct 14, 2025, 1PM

Title: Strategic planning for public transportation electrification: large-scale electric bus network transition planning via deep reinforcement learning

Speaker: Ms. Luyun Zhao (Department of Urban Planning and Design)

Date: Oct 14, 2025 (Tuesday)

Time: 1:00 pm - 2:00 pm

Venue: Room 8-28, Haking Wong Building, The University of Hong Kong

Registration Link: https://forms.office.com/r/FThKpBgpfp

ITS Student Committee will provide light refreshments and drinks for registered participants.

Abstract: Urban bus electrification is gaining global interest, playing a crucial role in reducing emissions. This study defines and addresses the electric bus network transition problem (EBNTP), jointly optimizing battery electric bus (BEB) fleet transitions and charging facility planning over a multi-period horizon. Existing research often neglects this interdependent long-term planning and lacks scalable solutions for large systems. This study proposes a deep reinforcement learning (DRL) approach, formulating EBNTP as a Markov Decision Process modeling sequential planning decisions, and introduces the DRL-HetGNN method, integrating heterogeneous graph neural networks (HetGNN) to capture network effects and enhance efficiency in large-scale applications. Using Hong Kong's franchised bus system as a case study, DRL-HetGNN demonstrates superior performance and generalizability compared to benchmark methods. Scenario analyses explore budget allocations, independent operators, BEB subsidies, and price fluctuations, while examining policy-incentive mechanisms to accelerate electrification. The findings will support policymakers in planning sustainable public transportation systems.

Bios: Luyun Zhao is a PhD candidate at the Department of Urban Planning and Design, Faculty of Architecture, HKU. Her research interest lies in public transit, shared mobility, transportation electrification, and transportation modeling. She has more than five years of theoretical and practical experience in the transportation industry. Prior to HKU, she worked at Tencent Smart Transportation, DiDi Chuxing Public Transportation Department and Two-Wheeler Department, Bytedance, and the World Bank. Luyun received her Bachelor of Engineering and Bachelor of Economics degrees from Peking University and her Master of City Planning degree from the University of Pennsylvania.