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SUMMARY:Seminar by Prof. Melvyn Sim\, National University of Singapore
DTSTART:20190815T150000
DTEND:20190815T163000
DTSTAMP:20260506T084526Z
UID:6a63274c49c1323b9339df098ae0c090fc8cfe1d56cbb9d0bd08a6ee
CATEGORIES:Conferences - Seminars
DESCRIPTION:Prof. Melvyn Sim\, National University of Singapore\nRobust Da
 ta-Driven Vehicle Routing with Time Windows \n\nAbstract\nOptimal routing 
 solutions in deterministic models usually fail to deliver promised on-time
  services in the real world of uncertainty\, causing potential loss of cus
 tomers and revenue. In this study\, we propose a new formulation for the d
 ata-driven Vehicle Routing Problem with Time Windows (vrptw) under uncerta
 in travel times that is compatible with the paradigm of distributionally r
 obust optimization. To mitigate the lateness as much as possible\, our mod
 el minimizes an innovative decision criterion on the delays\, termed the S
 ervice Fulfillment Risk Index (sri)\, while limiting the travel cost withi
 n a budget. The sri accounts for both the late arrival probability and its
  magnitude\, captures the risk and the Wasserstein ambiguity in travel tim
 es\, and is efficiently evaluable in closed form. In particular\, the clos
 ed-form solution reduces the vrptw under the Wasserstein ambiguity of inte
 rest to the problem under the empirical distribution with advanced deadlin
 es. To solve the problem\, we develop a Benders decomposition algorithm an
 d a variable neighborhood search heuristic\, and explore their speedup str
 ategies. We demonstrate their effectiveness through extensive computationa
 l studies. In particular\, our solution greatly improves on-time arrival p
 er- formance with slightly increased expenditure than the deterministic so
 lution. Our sri also outperforms the canonical decision criteria\, latenes
 s probability and expected lateness duration\, in out-of-sample simulation
 s. This is a joint work with with Yu Zhang\, Zhenzhen Zhang and Andrew Lim
 .\n 
LOCATION:ODY 4 03 https://plan.epfl.ch/?room==ODY%204%2003
STATUS:CONFIRMED
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