现邀请我校海外学者，利兹大学刘蓉晖教授来我校短期交流，安排两个学术报告，欢迎各位感兴趣的老师及同学参加。

　　讲座时间：2018 年4月4 日上午9:00-12:00

　　讲座地点：交大科技大厦1101会议室

　　主题：Bus Bunching

　　Introduction:

　　Headway fluctuation and “bus bunching” are well-known phenomena on many bus routes. Bus bunching occurs where one bus is delayed at upstream stops due to unplanned high boarding demand, or being delayed en-route by unforeseen traffic congestion. The subsequent service then has to pick up fewer passengers at that stop and departs earlier than scheduled.  At downstream stops the effect is than emphasised as the initial delay to the first vehicle and the early arrival of the subsequent service result in increasingly longer dwell times for the first bus and increasingly shorter dwell times for the second bus.

　　Talk 1  Considering Overtaking and Passenger Boarding Behaviour in Bus Holding to Reduce Bus Bunching

　　Bus holding control is a real-time control strategy used to reduce bus bunching. The holding control works by keeping buses adhere to a scheduled timetable and/or to a regular headway. In this talk, we consider the influence of bus driving behaviour and passenger boarding behaviour on the bus holding control and on bus bunching. We propose: (a) a distributed passenger boarding (DPB) behaviour to model the dynamic distribution of passengers, taking account of bus bunching at stops and bus capacity constraints; and (b) a first-depart-first-hold strategy for bus holding control. We show that when the combined overtaking and queue-swapping behaviour are considered, the proposed control strategies allowing for bus overtaking and DPB behaviour lead to better headway regularity, less passenger waiting time and less on-board travel time than when overtaking and DPB are not considered. We show that the benefit is even greater when travel time variability is higher and headway is smaller, suggesting that the control strategies are preferably deployed in high-frequency service.

　　Talk 2  On the effect of real time information on bus bunching (Napier)

　　Real time information allows passengers to time their arrival to bus stop so as to reduce their wait time. The aggregate result is a peaked passenger arrival distribution at bus stops, which has been shown to potentially lead to more serious bus bunching.  In this paper, we examine the trade-off between these two effects of real time information. We formulate an analytical model of information content (in terms of a predicted bus departure times) and information dissemination (in terms of its update frequency and reliability). We model passenger’s perception and response to information, and derive instantaneous arrival flows based on passengers’ risk-averse disutility to wait time and a penalty for missing the last attractive bus. We show that frequent information updates and moderately fuzzy (none precise) information can be helpful in spreading the passenger arrival times and reducing bus bunching. Crisp more accurate information may not always be the best for overall system performance. The results have implications on the design of real time information dissemination strategies.