Alignment: a collaborative, system aided, user driven ontology matching application


Alignment offers a simple GUI environment for matching two ontologies or vocabularies, with aid of con figurable similarity algorithms. Multiple users can work on the same project simultaneously. The application offers also social features, as users can upvote or downvote and comment, providing feedback on the produced linksets. The linksets are available through a SPARQL endpoint and an API. Alignment is the outcome of the experience working with heterogeneous public budget data, and has been used to align SKOS Vocabularies describing budget data across diverse administration levels of the EU and its member states.

The application is primarly used for manual linking between entities of two ontologies or vocabularies. The ontologies are presented as interactive foldable tree Graphs. A description of the selected entity is presented. Suggestions of best match are provided , by calculating string similarities. The user can then select one of the suggestions, if any, or select one of it's own. Afterwards, the user can select the type of link to create between predefined RDF links, or provide a custom RDF link. Created links can be exported on different RDF serializations and additionally stored on the application's database. Links can then be retrieved using our SPARQL Endpoint or an API, used for integration with non Semantic Web applications.

Alignment integrates the Silk Linking Framework functionality to calculate similarities between entities from different ontologies or vocabularies. To do this, a Silk confi guration fi le containing the comparison speci cations in the Link Speci cation Language of Silk (Silk LSL) and XML form has to be created and executed on the Silk Single Machine. The user can either select the default application settings as the comparison speci cations, or he can create his own confi guration file, customizing the similarity metrics that will be used in the comparison.

The application is provided as open source under MIT License on our Github repo.

Source Code:
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Open Knowledge Greece

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