“…To do this, a formal mechanism provided by topological modelling -continuous mappingcan be used. As it is stated in [7] and [39], "If some more detailed functioning system is formed by substitution of a subset of specialized functional features for some functional feature, then continuous mapping exists between a detailed model and a simplified parent topological model. In the topological digraph G* (X*, U*), the direction of arcs, which join the specialized point subset nodes with other nodes, is determined by the direction of the arcs, which join the replaced point with the corresponding nodes of the digraph G (X, U)".…”