Modeling Approaches for the Design and Analysis of Complex Systems

The design of a complex system traditionally relies on a systems engineering process that makes use of text documents and engineering data in multiple formats. The inherent limitations of the document-based manual approach have been targeted by the model-based systems engineering (MBSE) approach, promoted by the International Council on Systems Engineering (INCOSE), which defines MBSE as "the formalized application of modeling to support system requirements, design, analysis, verification, and validation activities beginning in the conceptual design phase and continuing throughout development and later life cycle" (INCOSE, 2007). In this respect, SysML (Systems Modeling Language) is the language that provides the modeling capability required in the systems engineering domain. SysML, which has been developed as an UML (Unified Modeling Language) extension, is now considered the standard modeling notation adopted in the MBSE context (OMG 2010). In addition, the recent adoption of the Business Process Modeling and Notation (BPMN) standard by the OMG (Object Management Group, the same body that defines and promotes UML and SysML), has introduced into the MBSE discipline the formalization of the business layer describing the interactions among the organizations that make use of systems at the context or operational scenario analysis level (OMG 2011). The advantages obtained by the MBSE approach, in terms of enhanced communications, reduced development risks, improved quality, increased productivity and enhanced knowledge transfer, can be further scaled up by innovative approaches that treat models as the primary artifacts of development, by increasing the level of automation throughout the system lifecycle.Such approaches have been introduced in the model-driven engineering (MDE) field and represent a radical shift from a merely contemplative use of models to a productive and more effective use (D. C. Schmidt, 2006). The application of MDE to systems engineering has been denoted as model-driven systems engineering (MDSE) (D. Gianni, A. D'Ambrogio and A. Tolk, 2014). MDSE applies metamodeling techniques and automated model transformations, introduced in the more general model-driven engineering context, to the systems engineering domain, thus boosting the aforementioned advantages of the MBSE approach. The talk first describes the principles and standards of MBSE and then focuses on MDSE approaches by illustrating their application to the simulation-based analysis of modern complex systems, i.e., large-scale heterogeneous systems, which are usually composed of several subsystems (P. Bocciarelli, A. D'Ambrogio and G. Fabiani 2012; P. Bocciarelli, A. D'Ambrogio, A. Giglio and D. Gianni, 2013).