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Abbreviated atomic-formula syntax

From: Drew McDermott <drew.mcdermott@yale.edu>
Date: Mon, 13 Oct 2003 19:45:47 -0400 (EDT)
Message-Id: <200310132345.h9DNjlu19035@pantheon-po04.its.yale.edu>
To: www-ws@w3.org, dejing.dou@yale.edu, peishen.qi@yale.edu


In his latest proposal for expression of conditional I/O and effects,
Mark Burstein came up with a very nice idea for expressing atomic
formulas:

	  <process:when>
	      <HasPwd>
		<client rdf:resource="#IClient"/>
		<userID rdf:resource="#LogInAcctName_"/>
		<password rdf:resource="#LogInPwd_"/>
		<toService rdf:resource="#IServer"/>
	      </HasPwd>
	  </process:when>

Here the 'when' construct expects a condition, and HasPwd supplies
one.  Basically, it's an object of type 'Atomic-formula', but with its
own syntax.  That is, the original way to express this in DRS would be
something like

     <drs:Atomic_formula>
         <rdf:subject rdf:resource="#IClient"/>
	 <rdf:predicate rdf:resource="#HasPwd-pred"/>
	 <rdf:object>
	    <drs:Term_seq rdf:parseType="Collection">
	       <rdf:_1 rdf:rsource="#LogInAcctName_"/>
	       <rdf:_2 rdf:resource="#LogInPwd_"/>
	       <rdf:_3 rdf:resource="#IServer"/>
	    </drs:Term_seq>
	 </rdf:object>
     </drs:Atomic_formula>
     
All we have to do is declare

    <owl:Class rdf:ID="HasPwd">
       <rdf:subClassOf rdf:resource="&drs;Atomic_formula"/>
    </owl:Class>

    <owl:Property rdf:ID="client">
       <rdfs:domain rdf:resource="#HasPwd"/>
    </owl:Property>

and similarly for 'userID', 'password', and 'toService'.  The
'rdfs:range's of 'client', 'userID', etc. are not so clear; they must
include both DRS terms and resources of the appropriate type.  Perhaps
not worth declaring.

I don't know why we didn't see this before; maybe everybody did but
me.  It's like allowing keyword syntax for atomic formulas as well as
positional syntax.

The paper about the DRS framework may be found at 
<a href="http://www.cs.yale.edu/~dvm/papers/McDermottDou02.pdf">Drew McDermott and Dejing Dou
 2002</a>  Representing disjunction and
quantifiers in RDF
{\it Proc. Int'l Semantic Web Conference}.

The DAML (not yet OWL) ontology for atomic formulas and such is 
<a href="http://cs-www.cs.yale.edu/homes/dvm/daml/drsonto.daml">here</a>.


                                             -- Drew

-- 
                                   -- Drew McDermott
                                      Yale Computer Science Department
Received on Monday, 13 October 2003 19:45:49 GMT

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