Models

The aim of the citybikes ontology network is to represent knowledge related to measurements (available bikes and free slots) made by the bike sharing systems in different cities of the world. Each of these measurements represents the state of a bike station in a particular place and time, and is conducted through a sensor in each bike station.

The citybikes ontology network follows a modular structure consisting of a central ontology (bikeSharing.owl file) that links together a set of ontologies that describe different sub domains involved in the modeling of the bike station measurements.

Following the approach proposed by the NeOn methodology it has been decided to develop the ontology network by reusing as many sources of knowledge (both ontological and non-ontological resources) as possible instead of building the network completely from scratch. In this way, we have selected the following resources to develop each of the sub domains listed:

  • Concepts specific to the domain: The citybikes ontology, http://citybikes.linkeddata.es/ontology#. The concepts that are specific are: bike sharing system and its name, and the bike station concept and its name, number, internal id, status, description, the number of boxes, free slots and free bikes.

  • Ids: The Dublin Core terms ontology, http://purl.org/dc/terms/. In particular, the identifier concept is reused.

  • Sensors and Observations: The Sensor ontology, http://purl.oclc.org/NET/ssnx/ssn#. In this context, there is a sensor in each bike station, and the observations are the number of available bikes and free slots at a certain date and time.

  • Latitude and longitude: The http://www.w3.org/2003/01/geo/wgs84_pos ontology. This is an ontology defined for geo positioning.

  • Timestamp: The Time ontology, http://www.w3.org/2006/time# where the timestamp is an instant.

  • Geospatial: The Geonames ontology, http://www.geonames.org/ontology#. It will be used to define the localization of the bike sharing systems and the stations. Services offered by Geonames will be used to define the location based on latitude and longitude of stations and systems.

    Figure 1

  • Quantity: the quantities, units and dimensions ontology, http://qudt.org/ . For the number of available bikes and free slots.

  • XMLSchema: Datatypes for Literals.

  • RDF Schema: For definining a hierarchy of classes and properties, and domain and range of properties.

Figure 1 shows the relation between the domain ontologies that formed the citybikes ontology network.

In this link you can find the current version of the citybikes ontology network.