  Empirical and numerical microscopic features of moving traffic jams are
presented. Based on a single vehicle data analysis, it is found that within
wide moving jams, i.e., between the upstream and downstream jam fronts there is
a complex microscopic spatiotemporal structure. This jam structure consists of
alternations of regions in which traffic flow is interrupted and flow states of
low speeds associated with "moving blanks" within the jam. Empirical features
of the moving blanks are found. Based on microscopic models in the context of
three-phase traffic theory, physical reasons for moving blanks emergence within
wide moving jams are disclosed. Structure of moving jam fronts is studied based
in microscopic traffic simulations. Non-linear effects associated with moving
jam propagation are numerically investigated and compared with empirical
results.
