Distributed Knowledge Representation on the Social Semantic Desktop: Named Graphs, Views and Roles in NRL

  • Michael Sintek
  • Ludger van Elst
  • Simon Scerri
  • Siegfried Handschuh
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4519)


The vision of the Social Semantic Desktop defines a user’s personal information environment as a source and end-point of the Semantic Web: Knowledge workers comprehensively express their information and data with respect to their own conceptualizations. Semantic Web languages and protocols are used to formalize these conceptualizations and for coordinating local and global information access. From the way this vision is being pursued in the NEPOMUK project, we identified several requirements and research questions with respect to knowledge representation. In addition to the general question of the expressivity needed in such a scenario, two main challenges come into focus: i) How can we cope with the heterogeneity of knowledge models and ontologies, esp. multiple knowledge modules with potentially different interpretations? ii) How can we support the tailoring of ontologies towards different needs in various exploiting applications?

In this paper, we present NRL, an approach to these two question that is based on named graphs for the modularization aspect and a view concept for the tailoring of ontologies. This view concept turned out to be of additional value, as it also provides a mechanism to impose different semantics on the same syntactical structure.

We think that the elements of our approach are not only adequate for the semantic desktop scenario, but are also of importance as building blocks for the general Semantic Web.


Semantic View Graph View View Concept Declarative Semantic Procedural Semantic 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Berlin Heidelberg 2007

Authors and Affiliations

  • Michael Sintek
    • 1
  • Ludger van Elst
    • 1
  • Simon Scerri
    • 2
  • Siegfried Handschuh
    • 2
  1. 1.Knowledge Management Department, German Research Center for Artificial Intelligence (DFKI) GmbH, KaiserslauternGermany
  2. 2.DERI, National University of Ireland, Galway 

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