International Journal of Knowledge Society Research (IJKSR), 3(4), p. 47-56 (2012); doi:10.4018/jksr.2012100105
The emerging Web of Data as part of the Semantic Web initiative and the sheer mass of information now available make it possible the deployment of new services and applications based on the reuse of existing vocabularies and datasets. A huge amount of this information is published by governments and organizations using semantic web languages and formats such as RDF, implicit graph structures developed using W3C standard languages: RDF-Schema or OWL, but new flexible programming models to process and exploit this data are required. In that sense the use of algorithms such as Spreading Activation is growing in order to find relevant and related information in this new data realm. Nevertheless the efficient exploration of the large knowledge bases has not yet been resolved and that is why new paradigms are emerging to boost the definitive deployment of the Web of Data. This cornerstone is being addressed applying new programming models such as MapReduce in combination with old-fashioned techniques of Document and Information Retrieval. In this paper an implementation of the Spreading Activation technique based on the MapReduce programming model and the problems of applying this paradigm to graph-based structures are introduced. Finally, a concrete experiment with real data is presented to illustrate the algorithm performance and scalability.