Merge branch 'issue-6' into 'develop-v2.1.1'

<p>In SAREF4WATR water infrastructures can be defined using the <a href="#s4watr:WaterInfrastructure">s4watr:WaterInfrastructure</a> class. Such infrastructures may be designed for one of the water types described above (through the <a href="#s4watr:isDesignedFor">s4watr:isDesignedFor</a> property), may have an intended use (through the <a href="#s4watr:isIntendedFor">s4watr:isIntendedFor</a> property), and may be classified into five different types, although others may be defined if needed: distribution systems (<a href="#s4watr:DistributionSystem">s4watr:DistributionSystem</a>), storage infrastructures (<a href="#s4watr:StorageInfrastructure">s4watr:StorageInfrastructure</a>), treatment plants (<a href="#s4watr:TreatmentPlant">s4watr:TreatmentPlant</a>), hydroelectric power plants (<a href="#s4watr:HydroelectricPowerPlant">s4watr:HydroelectricPowerPlant</a>), and monitoring infrastructures (<a href="#s4watr:MonitoringInfrastructure">s4watr:MonitoringInfrastructure</a>).</p>

<p>In order to represent the topology of a water infrastructure or its assets, the GeoSPARQL ontology has been reused and connected to the SARE4WATR terms. As shown in <a href="#Figure_10">Figure 10</a>, for representing spatial objects the geosp:SpatialObject class from GeoSPARQL has been reused along with its subclasses that allow defining spatial features (geosp:Feature) and geometries (geosp:Geometry). Different properties from GeoSPARQL can be reused to define spatial relations among spatial objects (e.g., geosp:sfContains, or geosp:sfWithin)or to define the geometry of a feature (geosp:hasGeometry). Two types of geometries from the GeoSPARQL Simple Features ontology are proposed to be used: points (sf:Point) and polygons (sf:Polygon), although others may also be used from that same ontology or from another one.

<p>In order to represent the topology of a water infrastructure or its assets, the GeoSPARQL ontology has been reused and connected to the SARE4WATR terms. As shown in <a href="#Figure_10">Figure 10</a>, for representing spatial objects the geo:SpatialObject class from GeoSPARQL has been reused along with its subclasses that allow defining spatial features (geo:Feature) and geometries (geo:Geometry). Different properties from GeoSPARQL can be reused to define spatial relations among spatial objects (e.g., geo:sfContains, or geo:sfWithin)or to define the geometry of a feature (geo:hasGeometry). Two types of geometries from the GeoSPARQL Simple Features ontology are proposed to be used: points (sf:Point) and polygons (sf:Polygon), although others may also be used from that same ontology or from another one.

We refer to the GeoSPARQL standard for further details on how to define the topology of water infrastructures.</p>

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