mapping different metadata standards

Hello,

I'm developing a secure P2P storage system that apart from storing  
the data of every contributing institution itself stores the  
according xml-metadata. This metadata is generated by the  
institutions according to different standards: i.e. METS, EAD, DC, etc.
The metadata of my distributed storage system will be modeled in RDF.  
In this RDF-Structure I want to integrate the (METS, EAD, DC)- 
Metadata of the stored files. In the future I want to perform  
searches over the whole P2P storage system. To be able to perform  
searches over the different metadata-standards I need to implement a  
semantic mapping between the different tags of the metadata- 
standards: i. e. dc:title eq. mets:title

It seems obvious to me that I should do this mapping by defining an  
ontology using rdfs and owl. But being new to this field it remains  
cumbersome how I'd have to code this. The w3c-documentation offers me  
little help because of its rather complicated language and limited  
usability of the examples..

Maybe some of you could help me with an example of such a mapping and  
a possible link to useful tools?

Thanks

Simon

--
Simon Margulies, lic. phil. hist.
University of Basel
Imaging & Media Lab
+41 61 267 04 88
http://www.distarnet.ch