Self-organized criticality in 1D traffic flow model with inflow or outflow

The asymmetric simple-exclusion model with parallel dynamics (the deterministic cellular automaton 184) is extended to take into account the exchange of cars between different lanes on a multi-lane roadway. The traffic flow model is presented by the one-dimensional asymmetric exclusion model with injection or extraction of particles. The system is driven asymptotically into a steady state exhibiting a self-organized criticality. The typical interval (s) between consecutive jams scales as (s) approximately=L v with v=0.62+or-0.04 where L is the system size. It is shown that the jam-interval distribution n s (L) satisfies the finite-size scaling form n s (L) approximately=L - beta f(s/L v ) with beta =2v.