The LCA platform has been developed by Synapta. It is aimed at a) integrating biographical metadata with open data from online sources, b) representing a complex and extensible knowledge base which also must be converted into Linked Data, c) allowing to add content both with automatic operations and manually, through a graphical interface, and d) publishing the resulting collection of ‘LCA files’ in a front-end website.
The system is based on an instance of Wikibase, the software developed by the Wikimedia Foundation to manage the Wikidata knowledge base. The LCA Wikibase is configured on the basis of a specific ontology. Custom software (a BOT) was configured for the first automated population of the system from different sources, basing on the open source project wikidata-edit.
Wikibase represents information in the form of subject-predicate-object declarations (statements), thus easing the task of mapping the data to RDF triples. Each declaration can be reified and annotated accordingly: it becomes the subject of a new triple by which it is possible, for example, to indicate the source or to specify a quality of the declaration itself. The combination of these features enables the LCA Project to bring the traditional manual data entry activity to the production and direct modification of Linked Data. Thanks to a fully automated system based on an open source project, LCA data are tripled and synchronized with an RDF triplestore, queried through a SPARQL endpoint.
Once data are converted to RDF, they can be enriched through interlinking operations with Linked Open Data from other databases.
Synapta developed for this purpose the OLAF tool, a crowdsourcing platform that supports semi-automatic interlinking. OLAF automatically identifies potential identity relations between LCA items and items available in external sources (in this case Wikidata and VIAF). These reports are subjected to manual verification and the validated data are recorded in the LCA Wikibase (and consequently in the LCA RDF triplestore) as identity relations of the type owl:sameAs.
Each LCA file has an author and data curator, who can consult, add and modify data in the Wikibase, and write the biographic texts on a suitably configured MediaWiki page. Both are hosted on the LCA project back-office site, data.leibnitiana.eu. In addition, a bibliography for each LCA item can be stored in the LCA Project's Zotero group library.
For each biographical entry, a web page is generated on this site by means of SPARQL live queries to the LCA triple-store, and to the Linked Open Data of other databases (through the already identified interlinks), to which the bibliography is also added live. Integration with Omeka as well as Zotero and DOI integration have been provided by ep for the LCA Project.