Gesellschaft für Mathematik und Datenverarbeitung mbH, St.Augustin, GMD-Bericht Nr. 176, 1989.
Abstract: This thesis defines and analyzes notions of specification, modularity and stepwise implementation for non-sequential systems. For this purpose the notion of Predicate-Event (PrE) nets is introduced and a theory of these nets is developed. Algebraic and net-theoretic properties of PrE nets are studied in the repsective framework.