Dear faculty members and fellow students,

You are cordially invited to attend my thesis defense.

Title: Design and Throughput Capacity Evaluation of Pickup and Dropoff (PUDO) Facilities

In-Person Location: Groseclose 403

Online Link: https://gatech.zoom.us/j/91929446962?pwd=Q0g5alV3V21uUnJLUjBDUUcybFFYQT09

Time: 3 - 5pm, Jul 9, 2024 (Tuesday)

Thesis Committee Members:

Dr. Anton Kleywegt (Advisor), School of Industrial and Systems Engineering, Georgia Institute of Technology

Dr. Hayriye Ayhan, School of Industrial and Systems Engineering, Georgia Institute of Technology

Dr. Xin Chen, School of Industrial and Systems Engineering, Georgia Institute of Technology

Dr. Srinivas Peeta, School of Civil and Environmental Engineering and School of Industrial and Systems Engineering, Georgia Institute of Technology

Dr. Yafeng Yin, Civil and Environmental Engineering Department and Industrial and Operations Engineering Department, University of Michigan

Abstract:

Pickup and drop-off (PUDO) facilities have long been important to facilitate passenger transportation and goods delivery. Typical examples of passenger PUDO facilities are expected at inter-mobility stations or terminals where passengers switch between different transportation modes, outside the stadiums where large-scale sports events or concerts are hosted, and at schools where students are dropped off in the morning and picked up in the afternoon. Meanwhile, the last mile of the urban freight delivery system has gauged unprecedented and continuing attention since the booming of e-commerce and time-sensitive delivery services, leading to frequent pickups and drop-offs of goods close to their end consumers. The recent increase in the adoption of on-demand transportation provided by transportation network companies, and the anticipated continuation of this trend with the introduction of self-driving vehicles, imply that PUDO facilities will become more widespread and substantial. The current practice of mostly using curbsides for PUDO operations will not be sustainable as demand increases. This dissertation presents stochastic modeling and computational tools to evaluate the throughput capacity of PUDO facilities in various contexts. We study the optimal design decisions and characterize near-optimal approximate policies to inform practical and implementable solutions in the real world.  A microscopic traffic simulation framework based on vehicle trajectory updates is developed for validation.

• In Chapter 1, we consider PUDO facilities with homogeneous spots and propose continuous-time Markov formulations to explicitly model the conflicting vehicle movements and the resultant delays. Traditional approaches such as queueing approximations often fail to do so and provide inaccurate calculations that are linear in facility size. We show the throughput capacity of PUDO facilities exhibit decreasing returns to scale.
• Chapter 2 presents practical insights into the design of layout configurations and operational policies of airport PUDO facilities. 
• In Chapter 3, we consider accessible PUDO facilities with spots of varying sizes and priorities for different classes of vehicles. We formulate a low-fidelity MDP and show the optimality of threshold policies, such that accessible spots can be assigned to vehicles with and without handicap registration as long as a sufficient number of them are available. The numerical results of a high-fidelity simulation validate that throughput capacity can be increased by constructing a relatively large number of accessible spots and allowing vehicles without handicap registration to use them subject to the threshold policies. 
• In Chapter 4, we consider the operational policy design problem for delivery bays with no demarcated spots. We specify a MDP and re-formulate multiple low-fidelity models that are easier to solve and that provide upper bounds on the system performance. We propose two approximate policies that are computationally efficient and demonstrate their near-optimality.