Keywords: Hierarchy; State machines; Modes; Heterogeneity; Modularity; Modeling; Semantics; Simulation; Cyber-physical systems
3rd International Workshop on Equation-Based Object-Oriented Modeling Languages and Tools; Oslo; Norway; October 3
 Ptolemy II Design Documents. Available at http: //ptolemy.eecs.berkeley.edu/ptolemyII/ designdoc.htm.
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