Shuai Li

Optimality Gap of Tailored Base-Surge Policies Decays Exponentially in Regular-Source Lead Times for Dual-Sourcing Models

  • Xin Chen
  • Shuai Li
  • Weijun Xie
    • Categories Dynamic Programming, Stochastic Programming, Supply Chain Management Tags , , , , ,

    This paper resolves an open problem posed in the literature by proving that, in dual-sourcing inventory systems, the optimality gap of tailored base-surge (TBS) policies decays exponentially with the regular source lead time, with the express-source lead time fixed. In contrast to the existing approach, which relies on conditional Jensen inequalities and a vanishing-discount argument … Read more

    Isotonic Optimization with Fixed Costs

  • Xin Chen
  • Shuai Li
  • Weijun Xie
    • Categories (Mixed) Integer Nonlinear Programming, Dynamic Programming, Supply Chain Management Tags , , ,

    This paper introduces a generalized isotonic optimization framework over an arborescence graph, where each node incurs state-dependent convex costs and a fixed cost upon strict increases. We begin with the special case in which the arborescence is a path and develop a dynamic programming (DP) algorithm with an initial complexity of $O(n^3)$, which we improve … Read more