Interlinking Linked Open Data datasets for learning
The environment is composed by two main modules: a mobile application, with a simple user interface that shows the information to the students during their visit, and a set of web services that elaborate the requests coming from the mobile application to provide interlinked information from DBpedia, Geonames, Europeana and, if available, datasets from the local municipality.
For instance the municipality of Palermo has already released the data about historical building in Open format; these data contain information related to opening hours, ticket costs, and other information under the responsibility of the municipality; by including the dataset provided by the municipality amongst the datasets used by the application, we can strongly enhance the descriptions already available on DBpedia and Europeana. When a student is visiting an area of the city, MELOD sends – at fixed intervals - his/her position to the server. The server uses the “Find nearby Wikipedia Entries “ service of the GeoNames API to establish if there are Wikipedia contents concerning sites to be visited in the students’ area (the extension of the area is pre-set by fixing its radius from the student position) . The list of sites will be sent to the mobile device and shown to the student. In a more complex scenario, student can select, before the visit, the main topics s/he is interested in. The list of topics is directly related to the DBpedia categories. In this way the system can filter the results to be shown to the students according to hisher/his choices and to the DBpedia category related to the sites. The student can decide to get more information about a specific site by clicking on its name on the list. When such a request arrives to the server, the DBpedia and Europeana datasets are used to search for more information.