Implementing CIDOC CRM Search Based on Fundamental Relations and OWLIM Rules

The CIDOC CRM provides an ontology for describing entities, properties and relationships appearing in cultural heritage (CH) documentation, history and archeology. CRM promotes shared understanding by providing an extensible semantic framework that any CH information can be mapped to. CRM data is usually represented in semantic web format (RDF) and comprises complex graphs of nodes and properties. An important question is how a user can search through such complex graphs, since the number of possible combinations is staggering. One approach "compresses" the semantic network by mapping many CRM entity classes to a few "Fundamental Concepts" (FC), and mapping whole networks of CRM properties to fewer "Fundamental Relations" (FR). These FC and FRs serve as a "search index" over the CRM semantic web and allow the user to use a simpler query vocabulary. We describe an implementation of CRM FR Search based on OWLIM Rules, done as part of the ResearchSpace (RS) project. We describe the technical details, problems and difficulties encountered, benefits and disadvantages of using OWLIM rules, and preliminary performance results. We provide implementation experience that can be valuable for further implementation, definition and maintenance of CRM FRs.