Modeling a system of systems to analyze requirements

To help systems engineers select a method for modeling large complex systems during the requirements phase of systems engineering, and also help researchers develop better models and methods, this paper identifies the semantics, mathematical basis, and attributes needed to model a system of systems. We use these model characteristics to compare several practical languages and methods that engineers use for systems engineering, Distributed Computing Design System (basis for Vitech´s method, CORE), Statemate, the Unified Modeling Language (UML), and Systems Modeling Language (SysML). We identify which methods excel in a specific area, and why. For example, we show why the method used in Statemate to control activities should be used in SysML.