Optimal Flows On Road Networks In Emergency Cases

Nicola Pasquino, Luigi Rarità

Centre of Research for Pure and Applied Mathematics c/o Department of Electronic and Computer Engineering University of Salerno Via Ponte Don Melillo, 84084, Fisciano (SA), Italy.
Department of Industrial Engineering University of Salerno Via Ponte Don Melillo, 84084, Fisciano (SA), Italy.

DOI: 10.4236/ojapps.2012.24B014                

Abstract

In this paper, we present a technique to redistribute car flows, described by a fluid dynamic model, on a portion of the Caltanissetta city, in Italy, when critical situations, such as car accidents, occur. Using a decentralized approach, a cost functional, that describes the asymptotic average velocity of emergency vehicles, is maximized with respect to distribution coefficients at simple junctions with two incoming roads and two outgoing ones. Then, in order to manage critical situations in high traffic conditions, local optimal coefficients at each node of the network are used. The overall traffic evolution is studied via simulations, that confirm the goodness of the optimization results. It is also proved that optimal coefficients allow a fast transit of emergency vehicles on assigned routes on the network.

Keywords

conservation laws; traffic problems; redistribution of flows

Conflicts of Interest

The authors declare no conflicts of interest.

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