service network design

Robust Continuous-Time Service Network Design under Travel Time Uncertainty

  • Shengnan Shu
  • Zhou Xu
  • Jin Qi
    • Categories Applications - OR and Management Sciences, Network Optimization, Robust Optimization Tags , , , , , ,

    The continuous-time service network design problem (CTSNDP) has wide applications in the field of transportation, but it is complicated by travel time uncertainty resulting from unpredictable traffic conditions. Incorporating uncertain travel times poses a significant challenge, as time-indexed mixed-integer linear programming (MILP) formulations commonly used to solve the CTSNDP with deterministic travel times become impractical. … Read more

    Integrating Order-to-Delivery Time Sensitivity in E-Commerce Middle-Mile Consolidation Network Design

  • Lacy M. Greening
  • Mathieu Dahan
  • Alan L. Erera
    • Categories Production and Logistics, Supply Chain Management, Transportation Tags , , ,

    This paper proposes an approach that leverages data on customer purchasing sensitivity to quoted order-to-delivery times (ODTs) when designing middle-mile consolidation networks to maximize the profit of e-commerce retailers. Our approach integrates quoted ODT-dependent sales volume predictions into a new mixed-integer program (MIP) that simultaneously determines ODT quotes and a consolidation plan, characterized by the … Read more

    Lead-Time-Constrained Middle-Mile Consolidation Network Design with Fixed Origins and Destinations

  • Lacy M. Greening
  • Mathieu Dahan
  • Alan L. Erera
    • Categories Applications - OR and Management Sciences, Transportation Tags , , ,

    Many large e-commerce retailers move sufficient freight volumes to operate private middle-mile consolidation networks for order fulfillment, transporting customer shipments from stocking locations to last-mile delivery partners in consolidated loads to reduce freight costs. We study a middle-mile network design optimization problem with fixed origins and destinations to build load consolidation plans that minimize cost … Read more

    Service Network Design for Same-Day Delivery with Hub Capacity Constraints

  • Haotian Wu
  • Ian Herszterg
  • Martin Savelsbergh
  • Yixiao Huang
    • Categories Applications - OR and Management Sciences, Transportation Tags , , ,

    We study a new service network design problem for an urban same-day delivery system in which the number of vehicles that can simultaneously load or unload at a hub is limited. Due to the presence of both time constraints for the commodities and capacity constraints at the hubs, it is no longer guaranteed that a … Read more

    Optimizing Package Express Operations in China

  • Martin Savelsbergh
  • Barış Yıldız
    • Categories Airline Optimization, Combinatorial Optimization, Transportation Tags , , ,

    We explore optimization models to support the planning and operations functions at package express carriers in China. The models simultaneously consider ground and air transportation, company-owned and purchased capacity, multiple service products, and shipments becoming available throughout the day. An extensive computational study using real-life data shows the efficacy of the models, provides insights into … Read more

    The Continuous Time Service Network Design Problem

  • Natashia Boland
  • Mike Hewitt
  • Luke Marshall
  • Martin Savelsbergh
    • Categories (Mixed) Integer Linear Programming, Transportation Tags , ,

    Consolidation carriers transport shipments that are small relative to trailer capacity. To be cost-effective, the carrier must consolidate shipments, which requires coordinating their paths in both space and time, i.e., the carrier must solve a Service Network Design problem. Most service network design models rely on discretization of time, i.e., instead of determining the exact … Read more