extending SAWSDL for XML instance semantic models

SAWSDL  provides a way to annotate the elements and attributes of an  
XML schema but I am also interested annotating the values in an  
instance of a schema document.  For example, section 4.1 of the SAWSDL  
Rec includes
<xs:simpleType name="Confirmation"
   sawsdl:modelReference="http://www.w3.org/2002/ws/sawsdl/spec/ontology/purchaseorder#OrderConfirmation 
">
   …
</xs:simpleType>
So I know what Confirmation means.  But if in the instance document I  
have

<Confirmation> partial </Confirmation>

how do I express a semantic model for the value partial?  partial may  
be a perfectly valid value from another vocabulary that is not  
included in the semantic model of Confirmation.

In practice, there is always a lot of attention paid to codifying the  
XML tags but in order to do an effective search, I also need to know  
the semantics of the target criteria.

I hope someone is still monitoring this mailing list and can weigh in  
on whether anyone has considered this before.

Thanks,

Ken


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Ken Laskey
MITRE Corporation, M/S H305      phone: 703-983-7934
7515 Colshire Drive                         fax:       703-983-1379
McLean VA 22102-7508