Figure 13
From: A unified framework for managing provenance information in translational research
RDF transitive closure using SPARQL ASK function. Computing transitive closure is a distinct feature of provenance queries, as the history of an entity is traced to its origin. Since the provenance query operators are implemented in SPARQL and SPARQL does not feature in-built support for computing transitive closure, the provenance query engine includes a module that uses the SPARQL ASK function to efficiently compute transitive closure over the <process, preceded_by> class-property pair.