Research Interests
The SUM Lab aims to address the questions, puzzles, and challenges that (will) arise in the incubation, development, and management of urban mobility services:
Mobility as a service, with particular interest for food/grocery delivery
The outbreak of COVID-19 pandemic has caused unprecedented damage to restaurant businesses. The downturn of dine-in services is projected to last for a long period as the public is reluctant to return to restaurants in fear of coronavirus exposure. In contrast, the online food ordering and delivery services, represented by DoorDash, Grubhub, and Uber Eats, filled in the vacancy and achieved explosive growth. The restaurant industry is experiencing a drastic change under the crossfire of these two driving forces. We are currently developing a low-cost but effective way to keep close track of the rapidly evolving market status. The product will be applied to quantify the damages caused by the pandemic to restaurant services and examine the disruptive impacts of delivery services in reshaping the demand structure of restaurant businesses.
Bridging fluid-based analysis and system uncertainty
As long-standing practices in transportation system analysis, we have been leveraging fluid models to help understand and manage systems with intrinsic uncertainty, such as carsharing and ridesharing service systems. By taking the deterministic analogs for random processes, fluid models yield considerable simplification and highlight the major physics underlying aggregate performance measures. However, a fundamental question often left behind in practice is how effective those resultant policies would be when applied back to the uncertain environment. We plan to address this neglected but critical question and seek instruments to quantify the efficacy of fluid-based analysis, which we believe will play bigger roles in system modeling and control. In fact, the interpretability and scalability of fluid models mean unbeatable advantages in coping with dynamic contexts, even when the latent uncertainty is better known.
Behavioral analytics and mechanism design
For human-centric mobility services, understanding travelers’ behavior and prescribing efficient management are always among the top-listed tasks for system operators and planners. However, despite an unprecedented amount of information produced, in terms of both quantity and quality, it has been less efficiently processed, analyzed, and shared among users, partially due to the gap between ideal theories and noisy realities. We thus aim to bridge the two by bringing closer the empirical analytics of user behaviors with the designs of strategies and mechanisms. Such in-depth coupling of theory and practice offer constructive insights to both the private stakeholders and the public agencies in mobility services.
Implications of electrification and automation on mobility services
In the foreseeable future, the entire auto industry will be in face of two consequential gear shifts, respectively being electrification and automation. The upcoming mobility system will almost certainly go through a lasting period, when fleets with different functions coexist in the service network. To prevent urban mobility services caught in the crossfire, we would like to join the on-going research quest to ready the system for smooth transitions. To prepare for the widespread adoption of electric vehicles, we want to understand the economic impact of electrification on urban mobility services and prescribe the optimal deployment of charging infrastructures to sustain the system operations through different stages of transitions. For vehicle automation, we are interested in the possible change of vehicle ownership and intend to study the potential business models and operations management for mobility services in the futuristic context. This exploration will help derive insights into regulating new mobility services and provide timely support for government agencies to develop policies to better manage the services.
Connecting and integrating mobility systems as an entirety
The transportation ecosystem is multimodal, involving driving, ride/car-pooling, transit, cycling, trucking, and even drone services shortly. Collectively, these activities increase urban and rural communities’ access to opportunities, contribute to the smart city initiatives, innovate system connections and integration. Mobility services, as increasingly important components of the ecosystem, should be seen and managed as a beneficial supplement rather than in isolation. We plan to enhance existing freight and passenger demand models to help government agencies to better assess the system-wide impacts of new services. We are particularly interested in the attempts that manage and connect the emerging services to strengthen the competitiveness of transit and to ensure sustainable system evolvement. We will develop novel models from a system’s perspective to prescribe optimal service selection and configuration to improve multimodal connections and promote system integration, with particular emphasis on those currently underserved groups/regions.
