摘要：Edutella is an RDF-based E-Learning P2P network that is aimed to accommodate heterogeneous learning resource metadata repositories in a P2P manner and further facilitate the exchange of metadata between these repositories based on RDF. Whereas Edutella provides RDF metadata repositories with a quite natural integration approach, XML metadata repositories have to overcome considerable incompatibility between XML’s tree-like hierarchical data model and RDF’s binary relational data model in order to be integrated into Edutella. In this paper we investigate a generic approach for integrating XML metadata repositories into Edutella in terms of an XQuery-enabled native XML database containing SCORM XML metadata. We first propose a triple-like XML-based common data view to cross incompatibility between arbitrary XML data model and RDF data model, then discuss the wrapper program implementation for XML metadata repositories based on the wrapper-like Edutella content provider integration architecture. At last, we propose a generic approach for querying complex XML data schemas in Edutella through QBE (Query by Example), and present the design of a QBE-based SCORM query GUI that can be used to query SCORM XML metadata in Edutella in the RDF syntax.
关键词：Resource Description Framework, Peer-to-Peer, XQuery, Sharable Content Object Reference Model, Query by Example
