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A threshold accepting approach to the open vehicle routing problem

Christos D. Tarantilis, George Ioannou, Chris T. Kiranoudis, Gregory P. Prastacos (2004)

RAIRO - Operations Research - Recherche Opérationnelle

In this paper we consider the operational planning problem of physical distribution via a fleet of hired vehicles, for which the travelling cost is solely a function of the sequence of locations visited within all open delivery routes, while vehicle fixed cost is inexistent. The problem is a special class of vehicle routing and is encountered in the literature as the Open Vehicle Routing Problem (OVRP), since vehicles are not required to return to the depot. The goal is to distribute in an optimal...

A threshold accepting approach to the Open Vehicle Routing problem

Christos D. Tarantilis, George Ioannou, Chris T. Kiranoudis, Gregory P. Prastacos (2010)

RAIRO - Operations Research

In this paper we consider the operational planning problem of physical distribution via a fleet of hired vehicles, for which the travelling cost is solely a function of the sequence of locations visited within all open delivery routes, while vehicle fixed cost is inexistent. The problem is a special class of vehicle routing and is encountered in the literature as the Open Vehicle Routing Problem (OVRP), since vehicles are not required to return to the depot. The goal is to distribute in an...

About the choice of the variable to unassign in a decision repair algorithm

Cédric Pralet, Gérard Verfaillie (2010)

RAIRO - Operations Research

The decision repair algorithm (Jussien and Lhomme, Artificial Intelligence139 (2002) 21–45), which has been designed to solve constraint satisfaction problems (CSP), can be seen, either (i) as an extension of the classical depth first tree search algorithm with the introduction of a free choice of the variable to which to backtrack in case of inconsistency, or (ii) as a local search algorithm in the space of the partial consistent variable assignments. or (iii) as a hybridisation between local...

About the choice of the variable to unassign in a decision repair algorithm

Cédric Pralet, Gérard Verfaillie (2005)

RAIRO - Operations Research - Recherche Opérationnelle

The decision repair algorithm (Jussien and Lhomme, Artificial Intelligence 139 (2002) 21–45), which has been designed to solve constraint satisfaction problems (CSP), can be seen, either (i) as an extension of the classical depth first tree search algorithm with the introduction of a free choice of the variable to which to backtrack in case of inconsistency, or (ii) as a local search algorithm in the space of the partial consistent variable assignments. or (iii) as a hybridisation between local...

Allocating servers to facilities, when demand is elastic to travel and waiting times

Vladimir Marianov, Miguel Rios, Francisco Javier Barros (2005)

RAIRO - Operations Research - Recherche Opérationnelle

Public inoculation centers are examples of facilities providing service to customers whose demand is elastic to travel and waiting time. That is, people will not travel too far, or stay in line for too long to obtain the service. The goal, when planning such services, is to maximize the demand they attract, by locating centers and staffing them so as to reduce customers’ travel time and time spent in queue. In the case of inoculation centers, the goal is to maximize the people that travel to the...

Allocating servers to facilities, when demand is elastic to travel and waiting times

Vladimir Marianov, Miguel Rios, Francisco Javier Barros (2006)

RAIRO - Operations Research

Public inoculation centers are examples of facilities providing service to customers whose demand is elastic to travel and waiting time. That is, people will not travel too far, or stay in line for too long to obtain the service. The goal, when planning such services, is to maximize the demand they attract, by locating centers and staffing them so as to reduce customers' travel time and time spent in queue. In the case of inoculation centers, the goal is to maximize the people that travel to the...

An ex-post bound on the greedy heuristic for the uncapacitated facility location problem

Jean-Michel Thizy (2006)

RAIRO - Operations Research

A bound for the greedy heuristic applied to the K-facility location problem can be calculated, using values gathered during the calculation of the heuristic. The bound strengthens a well-known bound for the heuristic. Computational experiments show that this bound can be beneficial when the number of facilities is small or close to the total number of potential sites. In addition, it is consistent with previous results about the influence of the data characteristics upon the optimal value.

Ant algorithm for flow assignment in connection-oriented networks

Krzysztof Walkowiak (2005)

International Journal of Applied Mathematics and Computer Science

This work introduces ANB (bf Ant Algorithm for bf Non-bf Bifurcated Flows), a novel approach to capacitated static optimization of flows in connection-oriented computer networks. The problem considered arises naturally from several optimization problems that have recently received significant attention. The proposed ANB is an ant algorithm motivated by recent works on the application of the ant algorithm to solving various problems related to computer networks. However, few works concern the use...

Complexity of partial inverse assignment problem and partial inverse cut problem

Xiaoguang Yang (2001)

RAIRO - Operations Research - Recherche Opérationnelle

For a given partial solution, the partial inverse problem is to modify the coefficients such that there is a full solution containing the partial solution, while the full solution becomes optimal under new coefficients, and the total modification is minimum. In this paper, we show that the partial inverse assignment problem and the partial inverse minimum cut problem are NP-hard if there are bound constraints on the changes of coefficients.

Complexity of Partial Inverse Assignment Problem and Partial Inverse Cut Problem

Xiaoguang Yang (2010)

RAIRO - Operations Research

For a given partial solution, the partial inverse problem is to modify the coefficients such that there is a full solution containing the partial solution, while the full solution becomes optimal under new coefficients, and the total modification is minimum. In this paper, we show that the partial inverse assignment problem and the partial inverse minimum cut problem are NP-hard if there are bound constraints on the changes of coefficients.

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