Figure 10 shows the first part of the PHYSSYS ontology that includes the three viewpoints (lines 2, 3 and 4) and relates the component and process views (definitions 5 and 6). The relation comp.proc (definition 5) implements the projection of simple components to process descriptions. Axiom 5a states that every atomic component must have a process description and axiom 5b that each mechanism must be part of the process description of a component. Axiom 5c ensures that a mechanism can only be part of one process description of one component. The fact that energy flows between process descriptions of two components must go through a connection is expressed by definition 6. For each connection between components, the process descriptions of these components must interact via an energy flow (axiom 6a). Vice versa, axiom 6b defines that an energy flow between the process descriptions of two components goes through a connection. Note that the relationship between the type of a connection and the number and domain of the energy flows of this connection has not been included in the excerpt.
Figure 10:
Excerpt from the first part of the PHYSSYS ontology where
components are projected onto physical processes. This is an example
of an ontology that only contains formalizations of the
interdependencies between the viewpoints it includes.