PER Transition Request
This is a transition request, and also serves as an agenda for a Transition Meeting with the Director.
We propose to publish the following documents as Proposed Edited Recommendation:
|owl2-overview||OWL 2 Web Ontology Language: Document Overview|
|owl2-syntax||OWL 2 Web Ontology Language: Structural Specification and Functional-Style Syntax|
|owl2-mapping-to-rdf||OWL 2 Web Ontology Language: Mapping to RDF Graphs|
|owl2-direct-semantics||OWL 2 Web Ontology Language: Direct Semantics|
|owl2-rdf-based-semantics||OWL 2 Web Ontology Language: RDF-Based Semantics|
|owl2-conformance||OWL 2 Web Ontology Language: Conformance|
|owl2-profiles||OWL 2 Web Ontology Language: Profiles|
|owl2-primer||OWL 2 Web Ontology Language: Primer|
|owl2-new-features||OWL 2 Web Ontology Language: New Features and Rationale|
|owl2-quick-reference||OWL 2 Web Ontology Language: Quick Reference Guide|
|owl2-xml-serialization||OWL 2 Web Ontology Language: XML Serialization|
|rdf-plain-literal||rdf:PlainLiteral: A Datatype for RDF Plain Literals|
The estimated publication date is 22 September, 2009.
2 Abstracts and Status Sections
For each document (except rdf-plain-literal), the abstract begins with a standard part:
The OWL 2 Web Ontology Language, informally OWL 2, is an ontology language for the Semantic Web with formally defined meaning. OWL 2 ontologies provide classes, properties, individuals, and data values and are stored as Semantic Web documents. OWL 2 ontologies can be used along with information written in RDF, and OWL 2 ontologies themselves are primarily exchanged as RDF documents. The OWL 2 Document Overview describes the overall state of OWL 2, and should be read before other OWL 2 documents.
(Note that in the Document Overview itself, the final sentence is omitted.)
This is followed by a short paragraph specific to the document in question, namely:
|Document||Second Part of Abstract|
|Document Overview||This document serves as an introduction to OWL 2 and the various other OWL 2 documents. It describes the syntaxes for OWL 2, the different kinds of semantics, the available profiles (sub-languages), and the relationship between OWL 1 and OWL 2.|
|Structural Specification and Functional-Style Syntax||The meaningful constructs provided by OWL 2 are defined in terms of their structure. As well, a functional-style syntax is defined for these constructs, with examples and informal descriptions. One can reason with OWL 2 ontologies under either the RDF-Based Semantics [OWL 2 RDF-Based Semantics] or the Direct Semantics [OWL 2 Direct Semantics]. If certain restrictions on OWL 2 ontologies are satisfied and the ontology is in OWL 2 DL, reasoning under the Direct Semantics can be implemented using techniques well known in the literature.|
|Mapping to RDF Graphs||This document defines the mapping of OWL 2 ontologies into RDF graphs, and vice versa.|
|Direct Semantics||This document provides the direct model-theoretic semantics for OWL 2, which is compatible with the description logic SROIQ. Furthermore, this document defines the most common inference problems for OWL 2.|
|RDF-Based Semantics||This document defines the RDF-compatible model-theoretic semantics of OWL 2.|
|Conformance||This document describes the conditions that OWL 2 tools must satisfy in order to be conformant with the language specification. It also presents a common format for OWL 2 test cases that both illustrate the features of the language and can be used for testing conformance.|
|Profiles||This document provides a specification of several profiles of OWL 2 which can be more simply and/or efficiently implemented. In logic, profiles are often called fragments. Most profiles are defined by placing restrictions on the structure of OWL 2 ontologies. These restrictions have been specified by modifying the productions of the functional-style syntax.|
|Primer||This primer provides an approachable introduction to OWL 2, including orientation for those coming from other disciplines, a running example showing how OWL 2 can be used to represent first simple information and then more complex information, how OWL 2 manages ontologies, and finally the distinctions between the various sublanguages of OWL 2.|
|New Features and Rationale||This document is a simple introduction to the new features of the OWL 2 Web Ontology Language, including an explanation of the differences between the initial version of OWL and OWL 2. The document also presents the requirements that have motivated the design of the main new features, and their rationale from a theoretical and implementation perspective.|
|Quick Reference Guide||This document provides a non-normative quick reference guide to the OWL 2 language. It also provides links to other documents, including the OWL 2 Primer for language introduction and examples, the OWL 2 Structural Specification and Functional Syntax document for more details of the functional syntax, and the OWL 2 New Features and Rationale document for new feature descriptions.|
|XML Serialization||This document specifies an XML serialization for OWL 2 that mirrors its structural specification. An XML schema defines this syntax and is available as a separate document, as well as being included here.|
The abstract for rdf:PlainLiteral is simply: This document presents the specification of a primitive datatype for the plain literals of RDF.
The Status sections are assembled automatically from maturity-specific and working-group specific boilerplate, along with this information about changes since the last publication:
The final product can be viewed as an editor's (publication preview) draft. A set of these drafts is linked from here:
3 Decision to Request PER
For all documents
For Plain Literal, there was also a decision by RIF:
4 Changes since CR
See the documents themselves:
All of these changes are minor and editorial.
5 Satisfies Group's Requirements
The requirements have not changed since the previous transition. None of the many reviews have claimed that the documents fail to satisfy the group's requirements.
The charter deliverables are by the group's publications, along with the test suite website.
The OWL 2 specification was originally written to have a normative reference to the following W3C specification that was, at that time, a Candidate Recommendation.:
This was addressed by making it temporarily a non-normative reference, as explained in the SOTD, with a view to re-publishing the OWL recommendation when XSD 1.1 became a recommendation. This has now happened:
The only group with a known dependency on OWL 2, at this time, is SPARQL-WG, which is currently not yet at CR.
7 Received Wide Review
See list of Last Call and CR phase comments :
More than 100 comments were received in response to the publication of the Last Call Working Drafts and Candidate Recommendations. These included reviews from other W3C Working and Interest Groups, W3C member organizations, and numerous companies.
8 Issues Formally Addressed
The current re-publication differs only w.r.t. the above mentioned reference to XSD 1.1, and some editorial changes in response to reported errata:
There have been no objections since the previous transition.
The group maintains a table of implementations.
So far, 18 Reasoner implementations are listed and 8 Editors, Development Environments or APIs. Of the 18 reasoners, 10 have reported test results.
- Three reasoners have reported results for OWL 2 DL, one of which (HermiT) passed all the approved tests, and one of which (Pellet) passed all but one of the approved tests (and for this test it was incomplete, not incorrect).
- Five reasoners have reported results for OWL 2 EL, three of which are "native" EL implementations, i.e., are implementations of algorithms whose complexity is polynomial with respect to the size of the ontology.
- Five reasoners have reported results for OWL 2 QL, two of which are "native" QL implementations, i.e., they implement algorithms that use query rewriting to access data stored in a relational database, and so have worst case complexity that is LOGSPACE with respect to the size of the data.
- Five reasoners have reported results for OWL 2 RL, two of which are "native" RL implementations, i.e., they are implemented using standard rule based technologies, and have worst case complexity that is polynomial with respect to the size of the ontology.
- Three reasoners have reported results for OWL 2 Full.
11 Patent Disclosures