ABSTRACT
The use of models in engineering and, in particular, in systems engineering, is very well established. With its roots in software engineering, there is the Unified Modeling Language (UML) and its extension to systems engineering, SysML, both managed by the Unified Modeling Group (UMG).2 The International Council on Systems Engineering (INCOSE) has a working group dedicated to modeling and associated tools,3 and there are numerous models promoted by individuals or small groups.4 It is probably fair to say that most of these modeling approaches result
in descriptions of aspects of the behavior of defined physical objects, even if most often based on the requirements of yet-to-be-designed objects, and they are therefore basically different to the approach proposed in this book, which links engineering with business through the concept of the service provided by the system. On the other hand, the modeling of economic performance is also well established,5 but lacks the direct link to engineering and design.
