Transportation

The two-echelon location-routing problem with time windows: Formulation, branch-and-price, and clustering

  • M. Saleh Farham
  • Cem Iyigun
  • Haldun Sural
    • Categories (Mixed) Integer Linear Programming, Transportation

    In this study, we consider the two-echelon location-routing problem with time windows (2E-LRPTW) to address the strategic and tactical decisions of the urban freight transportation. In the rst echelon, freights are delivered from city distribution centers (CDCs) to intermediate facilities, called satellites, in large batches. In the second echelon, goods are consolidated into smaller vehicles … Read more

    A Robust Rolling Horizon Framework for Empty Repositioning

  • Ilke Bakir
  • Alan L. Erera
  • Martin Savelsbergh
    • Categories Network Optimization, Robust Optimization, Transportation

    Naturally imbalanced freight flows force consolidation carriers to reposition resources empty. When constructing empty repositioning plans, the cost of repositioning resources empty needs to be weighed against the cost of corrective actions in case of unavailable resources. This is especially challenging given the uncertainty of future demand. We design and implement a robust rolling horizon … Read more

    Integrated Pricing and Routing on a Network

  • Pornpawee Bumpensanti
  • Martin Savelsbergh
  • He Wang
    • Categories Transportation Tags , , ,

    We consider an integrated pricing and routing problem on a network. The problem is motivated by applications in freight transportation such as package delivery and less-than-truckload shipping services. The decision maker sets a price for each origin-destination pair of the network, which determines the demand flow that needs to be served. The flows are then … Read more

    Solving Binary-Constrained Mixed Complementarity Problems Using Continuous Reformulations

  • Steven A. Gabriel
  • Martin Schmidt
  • Marina Leal
    • Categories (Mixed) Integer Nonlinear Programming, Complementarity and Variational Inequalities, Transportation Tags , , ,

    Mixed complementarity problems are of great importance in practice since they appear in various fields of applications like energy markets, optimal stopping, or traffic equilibrium problems. However, they are also very challenging due to their inherent, nonconvex structure. In addition, recent applications require the incorporation of integrality constraints. Since complementarity problems often model some kind … Read more

    Evaluating on-demand warehousing via dynamic facility location models

  • Kaan Unnu
  • Jennifer Pazour
    • Categories (Mixed) Integer Linear Programming, Supply Chain Management, Transportation Tags , , , , , ,

    On-demand warehousing platforms match companies with underutilized warehouse and distribution capabilities with customers who need extra space or distribution services. These new business models have unique advantages, in terms of reduced capacity and commitment granularity, but also have different cost structures compared to traditional ways of obtaining distribution capabilities. This research is the first quantitative … Read more

    Stochastic Last-mile Delivery with Crowd-shipping and Mobile Depots

  • Merve Bodur
  • Kianoush Mousavi
  • Matthew J. Roorda
    • Categories Stochastic Programming, Transportation Tags , , , , , ,

    This paper proposes a two-tier last-mile delivery model that optimally selects mobile depot locations in advance of full information about the availability of crowd-shippers, and then transfers packages to crowd-shippers for the final shipment to the customers. Uncertainty in crowd-shipper availability is incorporated by modeling the problem as a two-stage stochastic integer program. Enhanced decomposition … Read more

    Estimation of Marginal Cost to Serve Individual Customers

  • Jeffrey E. Arbogast
  • Chrysanthos E. Gounaris
  • Gildas Bonnier
  • Akang Wang
  • Zachary Wilson
    • Categories Supply Chain Management, Transportation Tags , , , ,

    This paper proposes a scenario sampling-based framework to estimate the expected incremental routing cost required so as to incorporate a target customer into an inherently stochastic supply chain network. Inspired from a real-life setting arising in the distribution of industrial gases, we demonstrate our framework and elucidate the quality of the marginal cost estimates it … Read more

    Substitution-based Equipment Balancing in Service Networks with Multiple Equipment Types

  • Natashia Boland
  • Alan L. Erera
  • Martin Savelsbergh
  • Yassine Ridouane
  • Yu Yang
    • Categories Applications - OR and Management Sciences, Transportation

    We investigate substitution-based equipment balancing for a package express carrier operating multiple equipment types in its service network. The weekly schedule of movements used to transport packages through the service network leads to changes in equipment inventory at the facilities in the network. We seek to reduce this change, i.e., the equipment imbalance associated with … Read more

    Dynamic programming for the time-dependent traveling salesman problem with time windows

  • Gonzalo Lera-Romero
  • Juan José Miranda-Bront
  • Francisco J. Soulignac
    • Categories Dynamic Programming, Transportation Tags , , , , ,

    The recent growth of direct-to-consumer deliveries has stressed the importance of last-mile logistics, becoming one of the critical factors in city planning. One of the key factors lies in the last-mile deliveries, reaching in some cases nearly 50% of the overall parcel delivery cost. Different variants of the the well-known Traveling Salesman Problem (TSP) arise … Read more

    Compact Formulations for Split Delivery Routing Problems

  • Pedro Munari
  • Martin Savelsbergh
    • Categories Branch and Cut Algorithms, Production and Logistics, Transportation Tags , , ,

    Split delivery routing problems are concerned with serving the demand of a set of customers with a fleet of capacitated vehicles at minimum cost, where a customer can be served by more than one vehicle if beneficial. They generalize traditional variants of routing problems and have applications in commercial as well as humanitarian logistics. Previously, … Read more