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             Department of Systems Engineering and Engineering Management
                     The Chinese University of Hong Kong

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Date: Friday, April 9, 2021, 16:30 to 17:30

Title: Dynamic Optimization Algorithms for Same-Day Delivery Problems

Speaker: Professor Manuel Iori, University of Modena and Reggio Emilia

Abstract:

In this talk, we will concentrate on a dynamic vehicle routing problem where stochastic customers request urgent deliveries characterized by restricted time windows. The aim is to use a fleet of vehicles to maximize the number of served requests and minimize the traveled distance. This problem is known in the literature as the same-day delivery problem and is of high importance because models a number of real-world applications, including the delivery of on-line purchases.
We solve the same-day delivery problem by proposing efficient solution algorithms, ranging from a simple reoptimization heuristic to a sophisticated branch-and-regret heuristic in which sampled scenarios are used to anticipate decisions. All algorithms adopt a tailored adaptive large neighborhood search to optimize the routing plans. We also present two new consensus functions to select routing plans for implementation, and propose strategies for determining the number and size of the sampled scenarios. The algorithms are also adapted to solve the problem variant where preemptive returns of the vehicles to the depot are allowed.
Extensive computational experiments on a large variety of instances prove the outstanding performance of the proposed algorithms, also in comparison with recent literature, in terms of served requests, traveled distance, and computing time. We will also discuss possible ways to adapt the proposed techniques to other problem variants that might be interesting for future researches.

Biography:

Manuel Iori is associate professor in operations research at the Department of Sciences and Methods of Engineering (DISMI) of the University of Modena and Reggio Emilia (UNIMORE), Italy.
His research activity concerns the development of mathematical models and solution algorithms for operations research, combinatorial optimization and logistics, with applications in domains such as vehicle routing, bin packing, knapsack, traveling salesman, parallel machine scheduling, and multidimensional cutting and packing.
He published more than 80 papers in peer-reviewed journals, including Operations Research, Mathematical Programming and Transportation Science. He participates to the program committees of the conferences EURO, Odysseus, ICCL, GECCO, LAGOS and Matheuristics. He is a collaborating member of CIRRELT, in Canada, and he spent research periods as visiting professor in Universities in Brazil, Canada, Chile, France, Great Britain and Spain.