Provenance 4th Face-to-Face Working Group Meeting

Posted on November 21, 2012 by Paul Groth

After an intense and fun week at the International Semantic Web Conference, I wanted to bring you up to date with the fourth face-to-face meeting of the Provenance Working Group. The meeting was held the two days before the start of ISWC and hosted by the W3C in their offices. We had 12 in-person participants and several who attended remotely on the phone.

The meeting was very productive. We resolved the last major outstanding issue in the PROV data model around the concept of mentionOf, which was designed to connect bundles of provenance together. Many in the working group felt that the concept was extremely useful in applications where provenance is collected by multiple parties over time, however, others felt that the concept was not precise nor well-understood. In the end, the group felt that it was too early to standardize the concept and instead agreed to produce a note and see if the community would use it. In addition, to this, we also resolved some other issues and went through the responses to public comments.

Getting ready for Candidate Recommendation

Importantly, we resolved to get ready for candidate recommendation on all of our major recommendations including the PROV data model, ontology, notation and constraints. In the coming weeks, you’ll see an announcement about this. This is an exciting moment as we believe the work is solid and ready for implementation.

Outreach

At the meeting we discussed outreach and in particular getting implementations. From an informal poll of the working group participants, we think we will have enough implementations to satisfy the requirements to go to proposed recommendation. In addition, we know from ISWC that a number of people are implementing as well. However, we want PROV to be widely adopted, so we hope you take the opportunity to implement the specifications and provide us an implementation report about your usage (more detail soon!). We are also in the process of adding additional material to make PROV easier to get into and also answer some frequently asked questions about it.

Thanks to our Reviewers

We’ve had quite a few public comments about the specs. Thanks to their comments, we have a much better set of documents.

Expect more announcements from us very soon as we make the final preparations leading to our next release of documents.

New SW Case Study by the Liverpool John Moores University

Posted on November 18, 2012 by Ivan Herman

The Liverpool John Moores University has provided a W3C Semantic Web Case Study on “Using the Semantic Web to Enhance the Teaching of Dance”. The case study describes how the Semantic Web can assist dancers, by tagging their video collections such that specific segments of choreography from across a dance project’s lifecycle may be easily found, compared, and cited in support of a dancer’s reflective diary entries.

Eleven SPARQL 1.1 Specifications Published

Posted on November 9, 2012 by Ivan Herman

The W3C SPARQL Working Group has published today a set of eleven documents, advancing most of SPARQL 1.1 to Proposed Recommendation. Building on the success of SPARQL 1.0, SPARQL 1.1 is a full-featured standard system for working with RDF data, including a query/update language, two HTTP protocols (one full-featured, one using basic HTTP verbs), three result formats, and other features which allow SPARQL endpoints to be combined and work together. Most features of SPARQL 1.1 have already been implemented by a range of SPARQL suppliers, as shown in our table of implementations and test results.

The Proposed Recommendations are:

  1. SPARQL 1.1 Overview - Overview of SPARQL 1.1 and the SPARQL 1.1 documents
  2. SPARQL 1.1 Query Language - A query language for RDF data.
  3. SPARQL 1.1 Update - Specifies additions to the query language to allow clients to update stored data
  4. SPARQL 1.1 Query Results JSON Format - How to use JSON for SPARQL query results
  5. SPARQL 1.1 Query Results CSV and TSV Formats - How to use comma-separated values (CVS) and tab-separated values (TSV) for SPARQL query results
  6. SPARQL Query Results XML Format - How to use XML for SPARQL query results. (This contains only minor, editorial updates from SPARQL 1.0, and is actually a Proposed Edited Recommendation.)
  7. SPARQL 1.1 Federated Query - an extension of the SPARQL 1.1 Query Language for executing queries distributed over different SPARQL endpoints.
  8. SPARQL 1.1 Service Description - a method for discovering and a vocabulary for describing SPARQL services.

The following are Candidate Recommendations, as the group still seeks more feedback from implementors:

  1. SPARQL 1.1 Entailment Regimes - defines the semantics of SPARQL queries under entailment regimes such as RDF Schema, OWL, or RIF.
  2. SPARQL 1.1 Protocol for RDF - A protocol defining means for conveying arbitrary SPARQL queries and update requests to a SPARQL service.
  3. SPARQL 1.1 Graph Store HTTP Protocol - As opposed to the full SPARQL protocol, this specification defines minimal means for managing RDF graph content directly via common HTTP operations.

The group has also produced a test suite and a page on using SPARQL 1.1 with RDF 1.1.

Proposed Edited Recommendations published for OWL 2

Posted on October 18, 2012 by Ivan Herman

The OWL Working Group has published twelve Proposed Edited Recommendations today, and two Working Group Notes. The main reason for the publication of an edited version is the fact that the “XML Schema Definition Language (XSD) 1.1, Part 2: Datatypes” has been recently published as a Recommendation. With the publication of XSD 1.1, the elements of OWL 2 which are based on XSD 1.1 are now considered required. Also, minor typographical errors and incorporation of editorial errata from the official OWL2 errata page have also been included.

Comments on the Proposed Edited Recommendations are welcome through 15 November. The documents are:

New release of the microdata to rdf mapping note

Posted on October 9, 2012 by Ivan Herman

The Semantic Web Interest Group has published a new version of the Group Note of Microdata to RDF.

HTML microdata is an extension to HTML used to embed machine-readable data into HTML documents. Whereas the microdata specification describes a means of markup, the output format is JSON. This specification describes processing rules that may be used to extract RDF from an HTML document containing microdata.

This update adds support for vocabulary expansion, for example to support features such as schema:additionalType. Microdata vocabulary expansion is a tiny subset of the RDFa vocabulary expansion but follows the same principle: the graph extracted from a microdata document is passed through a specific processor that adds additional triples to the graph (e.g., in the schema:additionalType case, it adds corresponding rdf:type triples).