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arXiv · cond-mat/9412045

Discrete stochastic models for traffic flow

Abstract

We investigate a probabilistic cellular automaton model which has been introduced recently. This model describes single-lane traffic flow on a ring and generalizes the asymmetric exclusion process models. We study the equilibrium properties and calculate the so-called fundamental diagrams (flow vs.\ density) for parallel dynamics. This is done numerically by computer simulations of the model and by means of an improved mean-field approximation which takes into account short-range correlations. For cars with maximum velocity 1 the simplest non-trivial approximation gives the exact result. For higher velocities the analytical results, obtained by iterated application of the approximation scheme, are in excellent agreement with the numerical simulations.

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M. Schreckenberg, A. Schadschneider, K. Nagel, N. Ito. 1994-12-09. Discrete stochastic models for traffic flow. https://doi.org/10.1103/physreve.51.2939

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