Transportation

A Shared Mobility Based Framework for Evacuation Planning and Operations under Forecast Uncertainty

  • Huiwen Jia
  • Siqian Shen
  • Kati Moug
    • Categories Network Optimization, Stochastic Programming, Transportation

    To meet evacuation needs from carless populations who may require personalized assistance to evacuate safely, we propose a ridesharing-based evacuation program that recruits volunteer drivers before a disaster strikes, and then matches volunteers with evacuees who need assistance once demand is realized. We optimize resource planning and evacuation operations under uncertain spatiotemporal demand, and construct … Read more

    Strategic Positioning of Empty Containers and Minimising Backhauls in Inland Supply Chain Network

  • Sajini Anand P S
  • Veena Bhat
    • Categories Applications - OR and Management Sciences, Network Optimization, Transportation

    An end-to-end supply chain operation for inland logistics requires coordination and planning among various operations of import pickups, export delivery and empty container positioning for reuse and evacuations of unused containers through the ports. A major business goal of all these operations focuses on reducing the transport costs by utilizing maximum network capacity across active … Read more

    Benders decomposition for Network Design Covering Problems

  • Victor Bucarey
  • Bernard Fortz
  • Martine Labbé
  • Juan A. Mesa
  • Natividad González-Blanco
    • Categories Facility Planning and Design, Transportation Tags , , ,

    We consider two covering variants of the network design problem. We are given a set of origin/destination(O/D) pairs and each such O/D pair is covered if there exists a path in the network from the origin to the destination whose length is not larger than a given threshold. In the first problem, called the maximal … Read more

    Exact and heuristic approaches to reschedule helicopter flights for personnel transportation in the oil industry

  • Yan Bastos
  • Jonathan De La Vega
  • Reinaldo Morabito
  • Pedro Munari
  • Roberto Tavares
  • Paulo César Ribas
  • Thiago Vieira
    • Categories Transportation Tags , , , , ,

    This paper addresses a real-life short-term rescheduling problem of helicopter flights from one onshore airport to several maritime units in the context of the oil industry. This is a complex and challenging problem to solve because of the particular characteristics observed in practice, such as pending flights transferred from previous days with different recovering priorities, … Read more

    An Integer L-shaped algorithm for the vehicle routing problem with time windows and stochastic demands

  • Jonathan De La Vega
  • Reinaldo Morabito
  • Pedro Munari
  • Fernando Ordóñez
  • Michel Gendreau
    • Categories Transportation

    This paper addresses the vehicle routing problem with time windows and stochastic demands (VRPTWSD). The problem is modeled as a two-stage stochastic program with recourse, in which routes are designed in the first stage and executed in the second. A failure occurs if the load of the vehicle is insufficient to meet the observed demand … Read more

    Branch-and-Refine for Solving Time-Dependent Problems

  • Armin Fügenschuh
  • Fabian Gnegel
    • Categories Combinatorial Optimization, Integer Programming, Transportation Tags , , ,

    One of the standard approaches for solving time-dependent discrete optimization problems, such as the traveling salesman problem with time-windows or the shortest path problem with time-windows, is to derive a so-called time-indexed formulation. If the problem has an underlying structure that can be described by a graph, the time-indexed formulation is usually based on a … Read more

    Vehicle Repositioning under Uncertainty

  • Qinshen Tang
  • Yu Zhang
  • Minglong Zhou
    • Categories Applications - OR and Management Sciences, Robust Optimization, Transportation Tags , ,

    We consider a general multi-period repositioning problem in vehicle-sharing networks such as bicycle-sharing systems, free-float car-sharing systems, and autonomous mobility-on-demand systems. This problem is subject to uncertainties along multiple dimensions – including demand, travel time, and repositioning duration – and faces several operational constraints such as the service level and cost budget. We propose a … Read more

    A multicommodity flow model for rerouting and retiming trains in real-time to reduce reactionary delay in complex station areas

  • Matthias Ehrgott
  • Stephen J. Maher
  • Edwin Reynolds
  • Anthony Patman
  • Judith Y.T. Wang
    • Categories Transportation Tags , , ,

    By rerouting and retiming trains in real-time, the propagation of reactionary delay in complex station areas can be reduced. In this study, we propose a new optimisation model and solution algorithm that can be used to determine the best combination of route and schedule changes to make. Whilst several models have been proposed to tackle … Read more

    Interdependence and Integration among Components of the Airline Scheduling Process: A State-of-the-Art Review

  • Divyam Aggarwal
  • Michael T. M. Emmerich
  • Dhish K. Saxena
    • Categories Airline Optimization, Scheduling, Transportation Tags , , , , , ,

    Over the last few decades, the Airline Scheduling Process (ASP) has received an unprecedented attention from airliners and operations research society. Conventionally, the Airline Scheduling Process is decomposed into four sub-problems namely-Schedule Generation, Fleet Assignment, aircraft Routing, and Crew Scheduling which are solved sequentially in order to incorporate tractability and feasibility in the overall process. … Read more

    The Multi-Stop Station Location Problem

  • Miriam Ganz
  • Erik Mühmer
  • Felix J. L. Willamowski
    • Categories Approximation Algorithms, Network Optimization, Transportation Tags , , , ,

    We introduce the (directed) multi-stop station location problem. The goal is to install stations such that ordered (multi-)sets of stops can be traversed with respect to range restrictions that are reset whenever a station is visited. Applications arise in telecommunications and transportation, e.g., charging station placement problems. The problem generalizes several network optimization problems such … Read more