General Overview

A graphical overview of the SAREF4SYST ontology is provided in Figure 1. In such figure:

• Rectangles are used to denote Classes. The label of the rectangle is the identifier of the Class. • Plain arrows are used to represent Object Properties between Classes. The label of the arrow is the identifier of the Object Property. The origin of the arrow is the domain Class of the property, and the target of the arrow is the range Class of the property. • Dashed arrows with identifiers between stereotype signs (i.e. "<< >>") refer to OWL axioms that are applied to some property. Four pairs of properties are inverse one of the other; the property s4syst:connectedTo is symmetric, and properties s4syst:hasSubSystem and s4syst:hasSubSystem are transitive. • A symbol =1 near the target of an arrow denotes that the associated property is functional. A symbol ∃ denotes a local existential restriction.

Systems and sub-systems

A s4syst:System, is defined as a part of the universe that is virtually isolated from the environment.

NOTE: The system properties are typically state variables (e.g. consumed or stored energy, agent population, temperature, volume, humidity).

A system may be connected to other systems that are part of its environment. This is modelled by a property named s4syst:connectedTo, which is symmetric.

Connections between systems

A connection between two s4syst:Systems, modelled by s4syst:connectedTo, describes the potential interactions between connected s4syst:Systems. A connection can be qualified using class s4syst:Connection.

Connection Points of systems

A s4syst:System connects to other s4syst:Systems at connection points. A connection point belongs to one and only one s4syst:System, and can be described using the class s4syst:ConnectionPoint.

One can then associate a s4syst:ConnectionPoint with properties (saref:Property) that describe it (e.g. position and speed, voltage and intensity, thermic transmission coefficient).