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326 Semantic as an Interoperability Enabler in Internet of Things
• A feature and property perspective, with a focus on features, properties
of them, and what can sense those properties.
Fig. 9.4 Overview of the Semantic Sensor Network ontology classes and properties.
The full ontology consists of 41 concepts and 39 object properties, that is, 117
concepts and 142 object properties in total, including those from DUL. The
SSN ontology is organized, conceptually but not physically, into ten modules,
that are described in the next paragraph and pointed out in the Figure 9.4.
• ConstraintBlock module: it is used to specify different ranges for
conditions on a system or sensor operation.
• Data module: the main task of this module is to manage data.
• Deployment module: it represents the main classes and properties
related to deployment of a network of sensors in the ontology.
• Device module: it provides the representation of sensors, describing
all its properties.
• MeasuringCapability module: it offers the measurement capabilities
of a sensor, for example, sensitivity, accuracy, precision,
latency, etc.
• OperatingRestriction module: it describes the operational and survival
restrictions of the System module.