Mobility-as-a-Service (MaaS) is an emerging business model integrating various travel modes into a single mobility service accessible on demand. Besides the ondemand mobility services, instant delivery services have increased rapidly and particularly boomed during the coronavirus (COVID-19) pandemic, requiring online orders to be delivered timely. In this study, to deal with the redundant mobility resources and high costs of instant delivery services, we model an MaaS ecosystem that provides mobility and instant delivery services by sharing the same multimodal transport system. We derive a two-class bundle choice user equilibrium (BUE) for mobility and delivery users in the MaaS ecosystems. We propose a bilateral surcharge-reward scheme (BSRS) to manage the integrated mobility and delivery demand in different incentive scenarios. We further formulate a bilevel programming problem to optimize the proposed BSRS, where the upper level problem aims to minimize the total system equilibrium costs of mobility and delivery users, and the lower level problem is the derived twoclass BUE with BSRS. We analyze the optimal operational strategies of the BSRS and develop a solution algorithm for the proposed bilevel programming problem based on the system performance under BSRS. Numerical studies conducted with real-world data validate the theoretical analysis, highlight the computational efficiency of the proposed algorithm, and indicate the benefits of the BSRS in managing the integrated mobility and delivery demand and reducing total system equilibrium costs of the MaaS ecosystems.
INTRODUCTIONThe coronavirus (COVID-19) outbreak has significantly impacted people's daily lives worldwide. To save lives and prevent the spread of COVID-19, more and more people have to stay home because of social distance guidelines, directives to stay home, and working from home. More than 3.9 billion people in over 90 countries or territories © 2022 Computer-Aided Civil and Infrastructure Engineering.have been asked or ordered to remain at home by their governments by April 2020. Meanwhile, those at home remain in need of essentials, such as medicine, meal, and food, therefore inducing a significant increase in the demand for online shopping and instant delivery services. 11 We use "instant delivery" in this study for the emphasis of the time emergency of the delivery, which is widely used in literature.