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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 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...

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 terminal area topology-independent GB-based conflict detection system for A-SMGCS.

Eugenio Roanes Lozano, Rafael Muga, Luis M. Laita, Eugenio Roanes Macías (2004)

RACSAM

A module for conflict detection in A-SMGCS is presented. It supervises the operations that the ground controller has to perform. It doesn?t depend on the topology of the terminal area. The system guarantees the safety of the proposed situation, that is, the impossibility that a conflict arises among aircrafts (and also road vehicles) obeying the signaling. We suppose that the terminal area has stop bars (or semaphores) controlling all intersections and accesses between runways, taxiways, exits,...

A variational model for equilibrium problems in a traffic network

Giandomenico Mastroeni, Massimo Pappalardo (2004)

RAIRO - Operations Research - Recherche Opérationnelle

We propose a variational model for one of the most important problems in traffic networks, namely, the network equilibrium flow that is, traditionally in the context of operations research, characterized by minimum cost flow. This model has the peculiarity of being formulated by means of a suitable variational inequality (VI) and its solution is called “equilibrium”. This model becomes a minimum cost model when the cost function is separable or, more general, when the jacobian of the cost operator...

A variational model for equilibrium problems in a traffic network

Giandomenico Mastroeni, Massimo Pappalardo (2010)

RAIRO - Operations Research

We propose a variational model for one of the most important problems in traffic networks, namely, the network equilibrium flow that is, traditionally in the context of operations research, characterized by minimum cost flow. This model has the peculiarity of being formulated by means of a suitable variational inequality (VI) and its solution is called “equilibrium”. This model becomes a minimum cost model when the cost function is separable or, more general, when the Jacobian of the cost operator...

A variational model for urban planning with traffic congestion

Guillaume Carlier, Filippo Santambrogio (2005)

ESAIM: Control, Optimisation and Calculus of Variations

We propose a variational model to describe the optimal distributions of residents and services in an urban area. The functional to be minimized involves an overall transportation cost taking into account congestion effects and two aditional terms which penalize concentration of residents and dispersion of services. We study regularity properties of the minimizers and treat in details some examples.

A variational model for urban planning with traffic congestion

Guillaume Carlier, Filippo Santambrogio (2010)

ESAIM: Control, Optimisation and Calculus of Variations

We propose a variational model to describe the optimal distributions of residents and services in an urban area. The functional to be minimized involves an overall transportation cost taking into account congestion effects and two aditional terms which penalize concentration of residents and dispersion of services. We study regularity properties of the minimizers and treat in details some examples.

Advanced approach for the public transportation regulation system based on cybercars

Asma Melki, Slim Hammadi, Yves Sallez, Thierry Berger, Christian Tahon (2010)

RAIRO - Operations Research

In the last decade, the authorities require the use of safe, comfortable vehicles to assure a door to door aspect with respect of environment in the urban context. In this paper, we propose an advanced approach of transport regulation where we integrate cybercars into a regulation process as an alternative in disruption cases. For that, we propose an ITS architecture including public transportation and cybercars into the same framework. We will show that collaboration between these two systems...

An autonomous vehicle sequencing problem at intersections: A genetic algorithm approach

Fei Yan, Mahjoub Dridi, Abdellah El Moudni (2013)

International Journal of Applied Mathematics and Computer Science

This paper addresses a vehicle sequencing problem for adjacent intersections under the framework of Autonomous Intersection Management (AIM). In the context of AIM, autonomous vehicles are considered to be independent individuals and the traffic control aims at deciding on an efficient vehicle passing sequence. Since there are considerable vehicle passing combinations, how to find an efficient vehicle passing sequence in a short time becomes a big challenge, especially for more than one intersection....

Cooperative driving at isolated intersections based on the optimal minimization of the maximum exit time

Jia Wu, Abdeljalil Abbas-Turki, Florent Perronnet (2013)

International Journal of Applied Mathematics and Computer Science

Traditional traffic control systems based on traffic light have achieved a great success in reducing the average delay of vehicles or in improving the traffic capacity. The main idea of these systems is based on the optimization of the cycle time, the phase sequence, and the phase duration. The right-of-ways are assigned to vehicles of one or several movements for a specific time. With the emergence of cooperative driving, an innovative traffic control concept, Autonomous Intersection Management...

Diseño de algoritmos para el problema del transporte escolar. Aplicación en la provincia de Burgos.

Joaquín A. Pacheco, Alberto Aragón, Cristina Delgado (2000)

Qüestiió

La problemática del transporte escolar es en Burgos especialmente significativa al ser una provincia extensa con muchos núcleos de población muy dispersos y poco poblados. En este trabajo se describen las aportaciones realizadas por los autores para dar solución a dicho problema, a través de técnicas que den soluciones lo más racionales posibles. En este sentido, hay que indicar que el término de racionalidad no sólo hace referencia a la minimización del coste total del transporte, sino también...

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