Browsing by Author "Gutierrez Jarpa, Gabriel"

Now showing 1 - 4 of 4
  • Thumbnail Image
    Item
    A branch-and-price algorithm for the Vehicle Routing Problem with Deliveries, Selective Pickups and Time Windows
    (ELSEVIER, 2010) Gutierrez Jarpa, Gabriel; Desaulniers, Guy; Laporte, Gilbert; Marianov, Vladimir
    In the Vehicle Routing Problem with Deliveries, Selective Pickups and Time Windows, the set of customers is the union of delivery customers and pickup customers. A fleet of identical capacitated vehicles based at the depot must perform all deliveries and profitable pickups while respecting time windows. The objective is to minimize routing costs, minus the revenue associated with the pickups. Five variants of the problem are considered according to the order imposed on deliveries and pickups. An exact branch-and-price algorithm is developed for the problem. Computational results are reported for instances containing up to 100 customers. (C) 2010 Elsevier B.V. All rights reserved.
  • Thumbnail Image
    Item
    Corridor-based metro network design with travel flow capture
    (2018) Gutierrez Jarpa, Gabriel; Laporte, Gilbert; Marianov Kluge, Vladimir
  • Thumbnail Image
    Item
    Lagrangean relaxation heuristics for the p-cable-trench problem
    (PERGAMON-ELSEVIER SCIENCE LTD, 2012) Marianov, Vladimir; Gutierrez Jarpa, Gabriel; Obreque, Carlos; Cornejo, Oscar
    We address the p-cable-trench problem. In this problem, p facilities are located, a trench network is dug and cables are laid in the trenches, so that every customer - or demand - in the region is connected to a facility through a cable. The digging cost of the trenches, as well as the sum of the cable lengths between the customers and their assigned facilities, are minimized. We formulate an integer programming model of the problem using multicommodity flows that allows finding the solution for instances of up to 200 nodes. We also propose two Lagrangean Relaxation-based heuristics to solve larger instances of the problem. Computational experience is provided for instances of up to 300 nodes. (C) 2011 Elsevier Ltd. All rights reserved.
  • Thumbnail Image
    Item
    Minimum cost path location for maximum traffic capture
    (PERGAMON-ELSEVIER SCIENCE LTD, 2010) Gutierrez Jarpa, Gabriel; Donoso, Macarena; Obreque, Carlos; Marianov, Vladimir
    A free path (with no preset extreme nodes) is located on a network, in such a way as to minimize the cost and maximize the traffic captured by the path. Traffic between a pair of nodes is captured if both nodes are visited by the path. Applications are the design of the route and locations of mailboxes for a local package delivery company, or the design of bus or subway lines, in which the shape of the route and the number of stops is determined by the solution of the optimization problem. The problem also applies to the design of an optical fiber network interconnecting WiFi antennas in a university campus. We propose two models and an exact solution method. Computational experience is presented for up to 300 nodes and 1772 arcs, as well as a practical case for the city of Concepcion, Chile. (C) 2009 Elsevier Ltd. All rights reserved.