- From: Yuzhong Qu <yzqu@seu.edu.cn>
- Date: Wed, 16 Feb 2005 14:11:26 +0800
- To: "SWIG" <semantic-web@w3.org>
- Message-ID: <00ad01c513ee$59377cc0$fd0b77ca@xobjects>
Two questions have not yet gotten answered. See below for more details. Thanks for your help in advance! Yuzhong Qu ----- Original Message ----- From: Yuzhong Qu To: www-rdf-interest@w3.org Cc: Peter F. Patel-Schneider Sent: Wednesday, October 13, 2004 2:35 PM Subject: Some fuzzy with cardinality restriction vs complex property in OWL The OWL S&AS says: To preserve decidability of reasoning in OWL Lite, not all properties can have cardinality restrictions placed on them or be specified as functional or inverse-functional. An individual-valued property is complex if 1/ it is specified as being functional or inverse-functional, 2/ there is some cardinality restriction that uses it, 3/ it has an inverse that is complex, or 4/ it has a super-property that is complex. Complex properties cannot be specified as being transitive. It seems OK, but some mistiness arises when diving into the deeps. We know that: someValuesFrom(owl:Thing) is logically equivalent to minCardinality(1) and someValuesFrom(SomeNonEmptyClass) logically implies minCardinality(1) My questions: 1. Suppose there is an existential restriction that uses a property, should the property be considered as a complex property? It seems not. But how to explain the implication of the above axioms? 2. Is there any meaning with minCardinality(0)? does it make the corresponding property become a complex property? e.g. restriction( myProperty minCardinality(0)) makes myProperty become a complex property? Thanks for your concern! Yuzhong Qu
Received on Wednesday, 16 February 2005 06:11:06 UTC