  We introduced a probability of traffic light, PL, at an intersection when
approaching cars in two roads are in same conditions. As a application, we
proposed a modified Nagel-Schreckenberg cellular automata model for describing
a conflicting vehicular traffic flow at the intersection. The results show that
the plateau region in the fundamental diagrams, caused by the effect of
interaction, is dependent not only on the probability PL, but also on the
adaptive schemes.
