Self e-Learning Networks (SeLeNes) aim at facilitating access to digital
material to a wide audience of learners and instructors with diverse
educational background and requirements. One step towards this goal is the
ability to specify educational needs or to describe educational material
according to personalized e-learning terminologies and conceptualizations.  

In this deliverable we investigate how this goal can be achieved in a
declarative way using language primitives for defining views over distributed,
autonomous RDF bases. Based on these primitives, we introduce a fully-fledged
view definition language, called RVL, for creating not only virtual resource
descriptions, but also virtual RDF/S schemas from (meta)classes, properties
and resource descriptions available on a SeLeNe.  Furthermore, we illustrate
how RVL views can be composed with structured RDF/S queries expressed in a
query language like RQL, by means of an internal logical framework (linear
Datalog rules) capturing the semantics of the RDF/S model, as well as of RQL
queries and RVL views. Finally, we present how the RQL/RVL query service can
be implemented in three different architectural alternatives: the centralized,
the mediated and the autonomous scenarios, as presented in Deliverable 5. In
particular, we introduce a framework for routing and processing RQL queries
and RVL views taking into account the data distribution (e.g., vertical,
horizontal) and optimization issues (e.g., data versus query shipping) in a
Peer-to-Peer database system.