DEVS specification for modeling and simulation of the UML activities

Recently, the existence of the foundational UML subset (fUML) has made a significant impact on driving the mainstream in behavioral modeling. Recent advances on concepts like UML actions and behavioral metamodeling promise better mechanisms in handling behavior. We argue that a greater potentiality can be achieved through establishing a rigorous mathematical grounding for the subset. We also argue that Parallel DEVS can be used as a suitable candidate. Thus, we propose formalizing the creation of UML activities as a set of atomic and coupled DEVS models. These abstractions have distinct structures and behaviors. That is to say, the foundational elements of UML activities and actions are modeled and mapped into a set of atomic as well as coupled models. Then, they can collectively serve as a basis for grounding different diagrams via coupling. We demonstrate the use of the formalism for the modeling and simulation of activities.