ANN: OWLDiff 0.1

On behalf of the Knowledge Based and Software Systems group at the Czech
Technical University in Prague, I am happy to announce the initial
release of the OWLDiff tool:

http://sourceforge.net/projects/owldiff

This Pellet-1.5.2-backed tool takes two OWL ontologies and
executes/visualizes their (syntactic) two-way diff together with :

    - entailment checking of the different axioms
    - entailment explanations
    - fully semantic CEX diff for EL :
http://www.webont.org/owled/2008dc/papers/presentation_12.pdf
    - merge of the performed changes
    - various visualization options
    - easy SVN integration

Our motivation for developing OWLDiff emerged during collaborative
ontology authoring and sharing through SVN, as it became quite difficult
to track changes in the same ontology made by other authors. Please find
full release notes attached. All feedback welcome !

Cheers,
Petr

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OWLDiff 0.1
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A tool to perform a 2-way diff of OWL ontologies.

* FEATURES *  
    - syntactic diff/merge functionality
    - explanations for inferred axioms
    - various visualization options - Manchester/DL syntax, classified view, plain axiom list
    - fully semantic diff for EL using the CEX algorithm.
    - easy Subversion integration
    
* PLAIN DIFF *
	- is provides an axiom by axiom difference of the ontologies
	- different axioms are shown in 'green', the common parts are blue (and hidden by default).
		
* ENTAILMENT CHECK *
	- for each axiom that is not contained in the other ontology an entailment check tests whether it can be derived from the other ontology or not. 
	- for inconsistent ontologies the entailment check is disabled

* CEX DIFF *
	- if either of the ontologies is not EL, no CEX is performed
	- axioms with colored background denote those that appear either in DiffR or DiffL list - they represent semantic differences between the classes the semantics of whose has changed 
	  (as described in http://www.webont.org/owled/2008dc/papers/owled2008dc_paper_12.pdf)

* ENTAILMENT EXPLANATIONS *
	- the incremental algorithm for single explanation generation is used (as described in Křemen, P. - Kouba, Z.: Incremental Approach to Error Explanations in Ontologies. In Proceedings of I-KNOW `07. Graz: Graz University of Technology, 2007, p. 332-339. ISSN 0948-695X )

Known Limitations :
	- imports are currently NOT resolved
	- just one explanation generated for a single axiom - TODO provide the possibility to get all explanations
	- usually the only sensible use is to compare ontologies with the same URI - no check is performed to find out whether the ontology/class/property/individual URI changed.

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2008 Czech Technical University, Knowledge Based and Software Systems Group
Petr Kremen, Marek Smid, Jan Abrahamcik, Jaroslav Pufler