Foreword
With the ubiquitous spread of potentially disruptive technology in our daily life, we face continuously, increasingly complex systems, and as engineers it is legitimate to ask ourselves whether we are still able to manage that complexity, whether requirements and specifications, as well as their verification and validation are still needed and even possible. Patrice Micouin’s book clearly answers “yes” and discusses a framework, both epistemological and practical, in order to address that challenge.
Patrice Micouin advocates a change of paradigm and introduces the Property-Model Methodology which relies on three claims:
All existing systems engineering processes call for an initial effort on having from the start testable, measurable and unambiguous requirements. However, the methodology developed by Patrice Micouin goes further, as it aims at cancelling any interpretation margin in the understanding of a requirement.
Such a paradigmatic change relies on the capacity of expressing specifications as membership constraints on the properties satisfied by the system and recursively its components (when condition C is fulfilled, property P should take its values in the given domain D of numerical values). Restricting the class of specifications in such a way is justified by an epistemological discussion inspired by Mario Bunge’s philosophy. Furthermore it should be noted that this class covers many real-world industrial applications and objectives in a much more immediate way than the behaviors obtained through simulation. Since such specifications build a semi-lattice, there is also a thorough way to go from system specification to component specifications, and back. On the one hand, this facilitates the transition from systems engineering to the different engineering disciplines needed to address individual components, and conversely. On the other hand, it avoids the usually tedious tasks of writing interface requirement specifications and interface definition documents.
As simulation is a common tool in many engineering disciplines, it is then much more straightforward to also use simulation as an effective tool at systems level, and engage in a paradigm transition from paper-centric engineering to model-based systems engineering. Practical efficiency considerations meet thus paradigmatic developments in this work, which is a landmark in the evolution of systems engineering practices that were formulated half a century ago when technology did not offer all the possibilities offered now.
Dr. Dominique LUZEAUX
Former Chairman of the French Chapter of INCOSE
July 2014