Title: Demand Management and Delivery Optimization for E-Retail Fulfillment

Abstract: Growing competition in the electronic retail (e-retail) sector has motivated firms to offer faster fulfillment time guarantees to customers. In particular, next-day delivery (NDD) and same-day delivery (SDD) options are now increasingly common in online marketplaces. This talk presents optimization models and solution methods for the design of SDD logistics systems with a focus on the “last mile” of the e-retail fulfillment supply chain. The first part of this talk studies fleet sizing for partitioning a SDD service region into single-vehicle delivery zones. The second part of the talk explores two alternate system designs: one in which the SDD service region is allowed to vary over time, and another in which a delivery fleet fulfills both SDD and NDD orders concurrently. The primary modeling approach used throughout is that of continuous approximations, in which exactly computed vehicle routes are replaced with their expected durations, and stochastic customer arrivals are replaced with deterministic accumulations; this approach captures average-case system behavior to facilitate high-level design and managerial insights. The resulting optimization problems are non-linear and non-convex, and significant attention is devoted to deriving structural properties and efficient algorithms for these problems. Case studies on real-world road networks in Miami, Phoenix, and Denver illustrate the practical applicability of these design techniques. The talk concludes with a discussion of potential future research directions, particularly in the area of sustainable and socially responsible e-commerce operations.

Biography: Dipayan Banerjee is a Ph.D. candidate in Operations Research at the Georgia Institute of Technology’s H. Milton Stewart School of Industrial and Systems Engineering (ISyE), where he is advised by Professors Alan Erera and Alejandro Toriello. He is broadly interested in optimization for logistics and supply chain management with a focus on the design and operation of modern e-commerce systems. His doctoral research is supported by the NSF Graduate Research Fellowship and the Dwight D. Eisenhower Transportation Research Fellowship. Dipayan was recently named a finalist for the 2023 INFORMS Transportation Science and Logistics Society Best Student Paper Award, and he was named a joint winner of the 2022-2023 ISyE Atlanta Air Cargo Association Fellowship for Ph.D. Research Excellence in Supply Chain Engineering. Dipayan previously completed his undergraduate studies in Industrial Engineering and Management Sciences from Northwestern University. His undergraduate research on public school transportation scheduling was named a finalist for the 2019 INFORMS Undergraduate Operations Research Prize.