Toward a rigorous interpretation of ESML-extended systems modeling language

Abstract

A graphics-based language known as ESML (extended systems modeling language), which is an extension of the data flow diagram notation for representing control logic in models of real-time systems, is analyzed and summarized to provide a rigorous interpretation of ESML symbols and their combinations. Based on elementary and compact (high-level) Petri nets (PNs), to which a succinct introduction is given, formal foundations for ESML, and in particular for its transformation schema (TS) notation, are proposed. Translation principles as well as examples of usual transformation and flow patterns are presented both in TS and PN notation. The resulting PN models are rigorous and accurate models of the dynamics of real-time systems with signals, prompts, and data flows of various kinds. Due to their formally defined token game they can be executed and used to study indeterminism and concurrency of events.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>