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On designing connected rapid transit networks reducing the number of transfers

Laureano Fernando Escudero, Susana Muñoz (2011)

RAIRO - Operations Research - Recherche Opérationnelle

In this paper we introduce some improvements on an approach that we described elsewhere for solving a modification of the well-known extended rapid transit network design problem. Firstly, we propose an integer programming model for selecting the stations to be constructed and the links between them, in such a way that a connected rapid transit network is obtained. Secondly, we consider a linear 0-1 programming model for determining a route of minimum length in the rapid transit network between...

On designing connected rapid transit networks reducing the number of transfers

Laureano Fernando Escudero, Susana Muñoz (2012)

RAIRO - Operations Research

In this paper we introduce some improvements on an approach that we described elsewhere for solving a modification of the well-known extended rapid transit network design problem. Firstly, we propose an integer programming model for selecting the stations to be constructed and the links between them, in such a way that a connected rapid transit network is obtained. Secondly, we consider a linear 0-1 programming model for determining a route of minimum...

On improving a solution to the ATSP with fixed origin and precedence relationships.

Laureano F. Escudero (1988)

Trabajos de Investigación Operativa

Given the directed graph G1 = (N, A1) with a node origin and a penalty matrix C, the ATSP with fixed origin and precedence relationships (hereafter, ASTP-PR) consists of finding the permutation of the nodes from the set N, such that it minimizes a matrix C based function and does not violate the precedence relationships given by the set A1. In this work we present an algorithm for improving a given feasible solution to the problem, by performing a local search that uses 3- and 4-change based procedures....

On modelling planning under uncertainty in manufacturing.

A. Alonso-Ayuso, L. F. Escudero, M.T. Ortuño (2007)

SORT

We present a modelling framework for two-stage and multi-stage mixed 0-1 problems under uncertainty for strategic Supply Chain Management, tactical production planning and operations assignment and scheduling. A scenario tree based scheme is used to represent the uncertainty. We present the Deterministic Equivalent Model of the stochastic mixed 0-1 programs with complete recourse that we study. The constraints are modelled by compact and splitting variable representations via scenarios.

On the convex hull of projective planes

Jean-François Maurras, Roumen Nedev (2008)

RAIRO - Operations Research

We study the finite projective planes with linear programming models. We give a complete description of the convex hull of the finite projective planes of order 2. We give some integer linear programming models whose solution are, either a finite projective (or affine) plane of order n, or a (n+2)-arc.

On the minimum cost multiple-source unsplittable flow problem

Meriema Belaidouni, Walid Ben-Ameur (2007)

RAIRO - Operations Research

The minimum cost multiple-source unsplittable flow problem is studied in this paper. A simple necessary condition to get a solution is proposed. It deals with capacities and demands and can be seen as a generalization of the well-known semi-metric condition for continuous multicommdity flows. A cutting plane algorithm is derived using a superadditive approach. The inequalities considered here are valid for single knapsack constraints. They are based on nondecreasing superadditive functions and...

Pickup and delivery problem with split demand and transfers

Jan Pelikán (2013)

Kybernetika

We deal with a logistic problem motivated by a case study from a company dealing with inland transportation of piece goods in regular cycles. The problem consists in transportation of goods among regional centres – hubs of a network. Demands on transportation are contained in a matrix of flows of goods between pairs of hubs. The transport is performed by vehicles covering the shipping demands and the task is to design a cyclical route and to place a depot for each vehicle. The route depot can be...

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