Introduction
Problem statement Modeling multi-dimensional systems In recent years increasing attention in system theory is paid to multi-dimensional dynamic systems. These so-called \gls{nD} systems are characterized by signals that depend on several independent variables. These variables can be for example time and space, in which case observations are not only correlated in time, but also in space. As an example, imagine a bridge or a mechanical structure. At discrete regular locations, sensors are placed that measure the local displacement (or acceleration) of the bridge over time....