Figure 12
From: A unified framework for managing provenance information in translational research
Architecture of the provenance query engine. The provenance query engine implements the four provenance query operators defined as part of the SPF and can be deployed over any RDF database that supports the standard RDFS entailment rules. The query engine consists of three components, to compose a SPARQL query pattern corresponding a query operator, a module to compute the transitive closure over the <process, preceded_by> class-property pair, and an optimization module that used the schema of the provenance ontology to materialize a RDF sub-graph to answer multiple provenance queries.