Improved decomposition of signal transition graphs

Signal Transition Graphs (STGs) are a version of Petri nets for the specification of asynchronous circuit behaviour. It has been suggested to decompose such a specification as a first step; this leads to a modular implementation, which can support circuit synthesis by possibly avoiding state explosion or allowing the use of library elements. In a previous paper, the original method was extended and shown to be much more generally applicable than known before. But further extensions are necessary, and some are presented in this paper, e.g.: to avoid dynamic auto-conflicts, the previous paper insisted on avoiding structural auto-conflicts, which is too restrictive; we show how to work with the latter type of auto-conflicts. This and another simple extension makes it necessary to restructure presentation and correctness proof of the decomposition algorithm