Seth Ladd's Blog

Pellet , an open source OWL reasoner from Mindswap , is now at version 1.3 . It is a very capable reasoner, and has excellent integration with Jena . Below is a list of changes for 1.3: * ENHANCED: SPARQL query engine PelletQueryExecution tu answer non-SELECT queries * ADDED: Processing class expressions in SPARQL queries * ADDED: Treating bnodes in SPARQL queries as non-distinguished variables * ADDED: Query optimization features (simplification and reordering). Reordering feature is disabled by default and needs to be enabled in the configuration file. * ENHANCED: Datatype reasoning support for user-defined datatypes * ADDED: Support for InverseFunctional datatype properties (a.k.a. keys). (experimental) * ADDED: Support for DL-safe rules (experimental) * ENHANCED: Pellet command line options * ENHANCED: More configuration parameters in pellet.properties

Henry has discovered SWOOP , a small ontology editor from MindSwap . This reminds me to point out a very nice feature of SWOOP, one that Protege does not have out of the box. SWOOP , through its integration with Pellet , is able to not only compute classifications but also able to tell you *why* your ontology is inconsistent. This, to me, is a huge step towards being able to use ontologies in "every day" problems. The use case here is: You are collecting information from many many different sources. You have an ontology that defines your view of the world. It's possible that all the different information sources will present to you conflicting information. Your ontology defines what is consistent, so therefore it should be able to tell you when you have information that is *inconsistent*. SWOOP does a pretty good job at giving you the feedback to find the source of the inconsistency. An example output is: Inconsistent ontology Reason: Individual ErrorBoat has m...