Semantic Web Languages
Antoine Isaac, Simon Schenk, Ansgar Scherp · 2011
The goal of this chapter is to make the reader familiar with relevant languages that address these two crucial matters: representing conceptual knowledge and querying resource description framework (RDF) data. With respect to conceptual knowledge, there exist very expressive languages such as OWL, which allow formal specification of the ontologies that guide the creation of RDF data and make it amenable to automated reasoning processes. However, OWL does not meet all conceptual representation requirements. The chapter introduces the Simple Knowledge Organization System (SKOS), which is suitable for modeling such lightweight ontologies. It introduces SPARQL, the recently standardized Semantic Web Query language, with an emphasis on aspects relevant to querying multimedia metadata in the running examples of COMM annotations. The chapter references relevant implementations, list limitations of SPARQL and give an outlook on possible future extensions to address these limitations. Controlled Vocabulary Terms knowledge representation languages; meta data; semantic Web