Designing Zonal-Based Flexible Bus Services Under Stochastic Demand

In this paper, we develop a zonal-based flexible bus services (ZBFBS) by considering both passenger demands’ spatial (origin-destination or OD) and volume stochastic variations. Service requests are grouped zonal OD pairs number of passengers per request, aggregated into demand categories which follow certain probability distributions. A two-stage program is formulated to minimize the expected operating cost ZBFBS, in visit sequences vehicles determined stage 1, whereas 2, service assigned either regular routes 1 ad hoc that incur additional costs. Demand reliability detour time introduced ensure quality separate problem two phases for efficient solutions. phase given requirements, services. optimize assignment cost. The reliabilities then optimized gradient-based approach sum We conduct numerical studies on vehicle capacity, limit demonstrate potential apply model Chengdu, China, based real data illustrate its applicability.