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A Hamilton-Jacobi approach to junction problems and application to traffic flows

Cyril Imbert, Régis Monneau, Hasnaa Zidani (2013)

ESAIM: Control, Optimisation and Calculus of Variations

This paper is concerned with the study of a model case of first order Hamilton-Jacobi equations posed on a “junction”, that is to say the union of a finite number of half-lines with a unique common point. The main result is a comparison principle. We also prove existence and stability of solutions. The two challenging difficulties are the singular geometry of the domain and the discontinuity of the Hamiltonian. As far as discontinuous Hamiltonians are concerned, these results seem to be new. They...

A heuristic column generation method for the heterogeneous fleet VRP

E. D. Taillard (2010)

RAIRO - Operations Research

This paper presents a heuristic column generation method for solving vehicle routing problems with a heterogeneous fleet of vehicles. The method may also solve the fleet size and composition vehicle routing problem and new best known solutions are reported for a set of classical problems. Numerical results show that the method is robust and efficient, particularly for medium and large size problem instances.

A hybrid approach for scheduling transportation networks

Mahjoub Dridi, Imed Kacem (2004)

International Journal of Applied Mathematics and Computer Science

In this paper, we consider a regulation problem of an urban transportation network. From a given timetable, we aim to find a new schedule of multiple vehicles after the detection of a disturbance at a given time. The main objective is to find a solution maximizing the level of service for all passengers. This problem was intensively studied with evolutionary approaches and multi-agent techniques, but without identifying its type before. In this paper, we formulate the problem as a classical one...

A hybrid genetic algorithm for the vehicle routing problem with three-dimensional loading constraints

Lixin Miao, Qingfang Ruan, Kevin Woghiren, Qi Ruo (2012)

RAIRO - Operations Research

This paper addresses a Three-Dimensional Loading Capacitated Vehicle Routing Problem (3L-CVRP) which combines a three-dimensional loading problem and vehicle routing problem in distribution logistics. The problem requires the combinatorial optimization of a feasible loading solution and a successive routing of vehicles to satisfy client demands, where all vehicles must start and terminate at a central depot. In spite of its clear practical significance...

A hybrid genetic algorithm for the vehicle routing problem with three-dimensional loading constraints

Lixin Miao, Qingfang Ruan, Kevin Woghiren, Qi Ruo (2012)

RAIRO - Operations Research

This paper addresses a Three-Dimensional Loading Capacitated Vehicle Routing Problem (3L-CVRP) which combines a three-dimensional loading problem and vehicle routing problem in distribution logistics. The problem requires the combinatorial optimization of a feasible loading solution and a successive routing of vehicles to satisfy client demands, where all vehicles must start and terminate at a central depot. In spite of its clear practical significance...

A Hybrid Procedure for Network Multi-Criteria Systems

Petr Fiala (2013)

Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica

Many of today’s systems are characterized by a network structure and evaluation of alternatives is based on multiple criteria. Network systems contain both positive and negative feedbacks. In the paper, a hybrid procedure is proposed for operation in network environment. The procedure is based on a combination of DEMATEL, ANP, and PROMETHEE approaches. DEMATEL is a comprehensive method for building and analyzing a structural model involving causal relationships between complex factors. For the network...

A linear programming approach to error bounds for random walks in the quarter-plane

Jasper Goseling, Richard J. Boucherie, Jan-Kees van Ommeren (2016)

Kybernetika

We consider the steady-state behavior of random walks in the quarter-plane, in particular, the expected value of performance measures that are component-wise linear over the state space. Since the stationary distribution of a random walk is in general not readily available we establish upper and lower bounds on performance in terms of another random walk with perturbed transition probabilities, for which the stationary distribution is a geometric product-form. The Markov reward approach as developed...

A Linguistic Fuzzy Approach to the Consensus Reaching in Multiple Criteria Group Decision-making Problems

Vojtěch Sukač, Jana Talašová, Jan Stoklasa (2016)

Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica

The paper introduces a new method of reaching a consensus in multiple criteria group decision-making under fuzziness. This model is based on the general definition of the ‘soft’ consensus introduced by Kacprzyk and Fedrizzi in 1986. The fuzzy evaluations of alternatives express degrees of fulfillment of the given goals by the respective alternatives for each expert. The selection of the best alternative is based on the fuzzy consensus by experts. For this purpose a set of alternatives which are...

A Markov chain model for traffic equilibrium problems

Giandomenico Mastroeni (2002)

RAIRO - Operations Research - Recherche Opérationnelle

We consider a stochastic approach in order to define an equilibrium model for a traffic-network problem. In particular, we assume a markovian behaviour of the users in their movements throughout the zones of the traffic area. This assumption turns out to be effective at least in the context of urban traffic, where, in general, the users tend to travel by choosing the path they find more convenient and not necessarily depending on the already travelled part. The developed model is a homogeneous Markov...

A Markov chain model for traffic equilibrium problems

Giandomenico Mastroeni (2010)

RAIRO - Operations Research

We consider a stochastic approach in order to define an equilibrium model for a traffic-network problem. In particular, we assume a Markovian behaviour of the users in their movements throughout the zones of the traffic area. This assumption turns out to be effective at least in the context of urban traffic, where, in general, the users tend to travel by choosing the path they find more convenient and not necessarily depending on the already travelled part. The developed model is a homogeneous...

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