Yu Yang

DeLuxing: Deep Lagrangian Underestimate Fixing for Column-Generation-Based Exact Methods

  • Yu Yang
    • Categories Branch and Cut Algorithms, Integer Programming, Transportation

    In this paper, we propose an innovative variable fixing strategy called deep Lagrangian underestimate fixing (DeLuxing). It is a highly effective approach for removing unnecessary variables in column-generation (CG)-based exact methods used to solve challenging discrete optimization problems commonly encountered in various industries, including vehicle routing problems (VRPs). DeLuxing employs a novel linear programming (LP) … Read more

    An exact price-cut-and-enumerate method for the capacitated multi-trip vehicle routing problem with time windows

  • Yu Yang
    • Categories (Mixed) Integer Linear Programming, Branch and Cut Algorithms, Transportation Tags , , ,

    We consider the capacitated multi-trip vehicle routing problem with time windows (CMTVRPTW), where vehicles are allowed to make multiple trips. The ability to perform multiple trips is necessary for some real-world applications where the vehicle capacity, the trip duration, or the number of drivers or vehicles is limited. However, it substantially increases the solution difficulty … Read more