Time: 10:00-11:30 am, November 10 (Thursday)

Conference No.: # Tencent Conference: 971-196-744

Reported by: Zhang Zhenzhen, associate professor of Tongji University

Introduction to the report:

The p-hub center problem is a fundamental model for the strategic design of hub location. It aims at constructing p fully interconnected hubs and links from nodes to hubs so that the longest path between any two nodes is minimized. Existing literature on the p-hub center problem under uncertainty often assumes a joint distribution of travel times, which is difficult (if not impossible) to elicit precisely. In this paper, we bridge the gap by investigating two distributionally robust chance constrained models, which cover the existing stochastic one with independent normal distribution and the sample average approximation approach as a special case, respectively. We derive deterministic reformulations as a mixed-integer program wherein a large number of constraints can be dynamically added via a constraint generation approach to accelerate computation. Extensive numerical experiments demonstrate the encouraging out-of-sample performance of our proposed models as well as the effectiveness of the constraint generation approach.

Brief introduction of the reporter:

Zhang Zhenzhen, associate professor and doctoral supervisor of the School of Economics and Management of Tongji University. Selected into the Shanghai High-level Talent Plan (2019). He once served as an assistant professor in the Department of Industrial Engineering of the National University of Singapore, and received a doctor's degree in the Department of Management Science of City University of Hong Kong, and a master's degree and a bachelor's degree in the Department of Computer Science of Xiamen University. He has long been committed to the theoretical research and algorithm design of large-scale integer programming and robust optimization, as well as the application in logistics and transportation planning, intelligent manufacturing, etc. Participated in solving many important enterprise problems, such as the transportation service procurement problem of Philips, the non-emergency ambulance scheduling problem of Hong Kong public hospitals, the commodity transfer problem of fast fashion brand CHARLES&KEITH, and the vehicle scheduling problem of Singapore logistics company. The research results obtained can help it significantly reduce its operating costs and significantly improve its service efficiency and service quality. At present, more than 20 SCI/SSCI journal papers have been published, including Operations Research (1), Transportation Science (3), Transportation Research Part B (3), etc. He is currently a member of the Technical Committee for Freight Planning and Logistics Management of the World Transport Congress (WTC), the Executive Secretary of the Transportation Branch of the Management Science and Engineering Society, and has been the reviewer of more than 30 internationally renowned journals for a long time.

(Undertaken by: Department of Management Science and Logistics, Scientific Research and Academic Exchange Center)