DEVS is closed under couplingBehavior of Coupled DEVS#References| . In other words, given a coupled DEVS model, its behavior is described as an atomic DEVS model. For a given coupled DEVS, once we have an equivalent atomic DEVS, behavior of can be referred to behavior of atomic DEVS which is based on Timed Event System. Similar to behavior of atomic DEVS, behavior of the Coupled DEVS class is described depending on definition of the total state set and its handling as follows.
View1: Total States = States * Elapsed Times
Given a coupled DEVS model, its behavior is described as an atomic DEVS model where
and are the input event set and the output event set, respectively.
is the internal state function. Given a partial state, the next state is given by
where
is the output function. Given a partial state,
View2: Total States = States * Lifespan * Elapsed Times
Given a coupled DEVS model, its behavior is described as an atomic DEVS model where
and are the input event set and the output event set, respectively.
is the partial state set where is the total state set of component .
is the initial state set where is the total initial state of component.
is the time advance function. Given,
is the external state function. Given a total state where, and input event, the next state is given by
where
and
Given the partial state, let denote the set of imminent components. The firing component which triggers the internal state transition and an output event is determined by
is the internal state function. Given a partial state, the next state is given by
Since in a coupled DEVS model with non-empty sub-components, i.e.,, the number of clocks which trace their elapsed times are multiple, so time passage of the model is noticeable. ;For View1 Given a total state where If unit event segment is the null event segment, i.e. , the state trajectory in terms of Timed Event System is
; For View2 Given a total state where If unit event segment is the null event segment, i.e. , the state trajectory in terms of Timed Event System is
Remarks
The behavior of a couple DEVS network whose all sub-components are deterministic DEVS models can be non-deterministic if is non-deterministic.
