From “Formal Methods” to System Modeling - Formal Methods and Hybrid Real-Time Systems - page 30

is abstraction of

is refined to

interface model

Implements/is abstracted to

is composed to

composed system model

state machine model

process model

isbasedon

Data model

Fig. 2. Meta Model of the System Model

Typical description techniques are axiomatic, algebraic specification (abstract data
types, see [1]), Entity/Relationship-diagrams or class diagrams.

4.2.2 State Model
State machines give a basic view onto interactive systems. A state machine is
described by a set of states called a state space, a subset of the state set called initial
states, and a state transition function.
Typical we work with state machines with labeled or with unlabelled transitions.
As labels we use the elements of a given set of actions. Another class is state
machines with input and output. We distinguish this the following classes of state
transition functions:

Δ : State → ℘ (State) unlabeled state transitions

Δ : Action → (State → ℘ (State)) action labeled state transitions

Output) state transitions with input and output
In the case of a state machine with input and output we may consider pairs of input
and output as labels. The description of the state space and the label sets Action, Input
and Output is again a data-modeling task. A simple and powerful way to define a state

Δ : State × Input → ℘ (State ×