Posts Tagged ‘OWL 2’

W3C’s Semantic Web Activity Folds Into New Data Activity

rsz_w3clogoThe World Wide Web Consortium has headline news today: The Semantic Web, as well as eGovernment, Activities are being merged and superseded by the Data Activity, where Phil Archer serves as Lead.  Two new workgroups also have been chartered: CSV on the Web and Data on the Web Best Practices.

What’s driving this? First, Archer explains, the Semantic Web technology stack is now mature, and it’s time to allow those updated standards to be used. With RDF 1.1, the Linked Data Platform, SPARQL 1.1, RDB To RDF Mapping Language (R2RML), OWL 2, and Provenance all done or very close to it, it’s the right time “to take that very successful technology stack and try to implement it in the wider environment,” Archer says, rather than continue tinkering with the standards.

The second reason, he notes, is that a large community exists “that sees Linked Data, let alone the full Semantic Web, as an unnecessarily complicated technology. To many developers, data means JSON — anything else is a problem. During the Open Data on the Web workshop held in London in April, Open Knowledge Foundation co-founder and director Rufus Pollock said that if he suggested to the developers that they learn SPARQL he’d be laughed at – and he’s not alone.” Archer says. “We need to end the religious wars, where they exist, and try to make it easier to work with data in the format that people like to work in.”

The new CSV on the Web Working Group is an important step in that direction, following on the heels of efforts such as R2RML. It’s about providing metadata about CSV files, such as column headings, data types, and annotations, and, with it, making it easily possible to convert CSV into RDF (or other formats), easing data integration. “The working group will define a metadata vocabulary and then a protocol for how to link data to metadata (presumably using HTTP Link headers) or embed the metadata directly. Since the links between data and metadata can work in either direction, the data can come from an API that returns tabular data just as easily as it can a static file,” says Archer. “It doesn’t take much imagination to string together a tool chain that allows you to run SPARQL queries against ’5 Star Data’ that’s actually published as a CSV exported from a spreadsheet.”

Read more

Introduction to: Reasoners

Name Tag: Hello, we are ReasonersReasoning is the task of deriving implicit facts from a set of given explicit facts. These facts can be expressed in OWL 2 ontologies and stored RDF triplestores. For example, the following fact: “a Student is a Person,” can be expressed in an ontology, while the fact: “Bob is a Student,” can be stored in a triplestore. A reasoner is a software application that is able to reason. For example, a reasoner is able to infer the following implicit fact: “Bob is a Person.”

Reasoning Tasks

Reasoning tasks considered in OWL 2 are: ontology consistency, class satisfiability, classification, instance checking, and conjunctive query answering.

Read more

Introduction to: OWL Profiles

Name Tag: Hello, we are the OWL familyOWL, the Web Ontology Language has been standardized by W3C as a powerful language to represent knowledge (i.e. ontologies) on the Web. OWL has two functionalities. The first functionality is to express knowledge in an unambiguous way. This is accomplished by representing knowledge as set of concepts within a particular domain and the relationship between these concepts. If we only take into account this functionality, then the goal is very similar to that of UML or Entity-Relationship diagrams. The second functionality is to be able to draw conclusions from the knowledge that has been expressed. In other words, be able to infer implicit knowledge from the explicit knowledge. We call this reasoning and this is what distinguishes OWL from UML or other modeling languages.

OWL evolved from several proposals and became a standard in 2004. This was subsequently extended in 2008 by a second standard version, OWL 2. With OWL, you have the possibility of expressing all kinds of knowledge. The basic building blocks of an ontology are concepts (a.k.a classes) and the relationships between the classes (a.k.a properties).  For example, if we were to create an ontology about a university, the classes would include Student, Professor, Courses while the properties would be isEnrolled, because a Student is enrolled in a Course, and isTaughtBy, because a Professor teaches a Course.

Read more

New Paper — OWL: Yet to Arrive on the Web of Data?

A new paper is currently available for download entitled OWL: Yet to arrive on the Web of Data? The paper was written by Birte Glimm, Aidan Hogan, Markus Krötzsch, and Axel Polleres. The abstract states, “Seven years on from OWL becoming a W3C recommendation, and two years on from the more recent OWL 2 W3C recommendation, OWL has still experienced only patchy uptake on the Web. Although certain OWL features (like owl:sameAs) are very popular, other features of OWL are largely neglected by publishers in the Linked Data world.” Read more

SKOS and OWL 2 are Now Interoperable

In tech news, SKOS has been altered to interoperate with OWL 2. Up until now the two vocabularies haven’t been able to “play together nicely,” but thanks to a few simple tweaks to SKOS, they are now able to operate together smoothly.

According to the article, “In the semantic Web, arguably SKOS is the right vocabulary for representing simple knowledge structures, and OWL 2 is the right language for asserting axioms and ontological relationships. In the early days we chose a reliance on SKOS for the UMBEL reference concept ontology, because of UMBEL’s natural role as a knowledge structure.” Read more

Introducing OWL 2: A Panel and Community Discussion – SemTech 2009 Audio

Michael A Smith, Clark & Parsia LLC
Deborah L. McGuinness, Rensselaer Polytechnic Institute (RPI)
Ivan Herman, World Wide Web Consortium
Zhe Wu, Oracle Corp.
Ian Horrocks, Oxford University

OWL 2 is the first major revision of OWL, a key semantic technology standard, and is on-track to become a W3C standard in late Spring 2009, just in time for a panel-led community discussion about the opportunities provided by OWL 2.

The panel will be composed of acknowledged OWL 2 experts who’ve helped shape the new revision, including Ivan Herman, Semantic Web lead at W3C; Deborah McGuinness, well-known educator and researcher in ontology-based computing; as well as vendor representatives from Oracle and Clark & Parsia LLC.

The conversation will focus on new features of OWL 2, including the new profiles, as well as usability enhancements that make OWL 2 better suited for a wide-range of real world problems. The panelists will also give insights into the general trends for OWL and OWL 2 adoption among business, government, health care, and related fields. The panel will speak to the rationale behind many design decisions and provide unique insight into the issues surrounding successful adoption of OWL 2. There will be ample opportunity for the audience to shape the discussion during Q&A.

Attachment: Introducing OWL- A Panel and Community Discussion.mp3 (50.78 MB)

Presenters:

Michael Smith
Michael Smith
Clark & Parsia LLC

Mike Smith is a Senior Engineer at Clark & Parsia LLC, a software
development and consulting firm specializing in the development and
application of artificial intelligence technologies. Mike is a member
of the W3 OWL WG, participates actively in the OWL community, and
publishes content at http://clarkparsia.com/weblog/ He is one of the
primary developers of Pellet, the open source OWL reasoner, and
contributes to the Protégé and OWL API projects. He holds B.S. and
M.S. degrees in Systems and Information Engineering from the
University of Virginia.

Ivan Herman
Ivan Herman
World Wide Web Consortium
See http://www.ivan-herman.net

Ian Horrocks
Ian Horrocks
Oxford University

Ian Horrocks is a Fellow of Oriel College Oxford and a Professor in the Oxford University Computing Laboratory. He is internationally recognised for his work on ontology languages and reasoning systems. He was centrally involved in the development of the OIL, DAML+OIL and OWL ontology languages, and is co-chair of the W3C Working Group that is developing OWL 2. He has published more than 150 articles in conferences, journals and books. In 2005 he received the BCS Roger Needham award for his his pioneering work in the Semantic Web and was also awarded an EPSRC Senior Research Fellowship.

Deborah McGuinness
Deborah McGuinness
Rensselaer Polytechnic Institute (RPI)

Professor Deborah McGuinness is co-directing the Tetherless World Constellation at Rensselaer Polytechnic Institute. For the previous 9 years Dr McGuinness led or co-led the Knowledge Systems Lab at Stanford University. Dr. McGuinness is a leading expert in knowledge representation and reasoning languages and systems, and has worked in ontology creation and evolution environments for over 25 years. She has done foundational work in ontologies, having built and deployed numerous ontological environments during the course of her career in AT&T Bell Laboratories and Lucent Technologies. Her work on languages (including OWL, DAML+OIL, OIL, CLASSIC) is aimed at providing languages that enable the next generation of web applications. She leads efforts at RPI on among other things, explainable systems, accountable social collaborative environments, and semantic eScience. She is on numerous advisory boards for academic and commercial startups and serves as CEO of McGuinness Associates.

Zhe Wu
Zhe Wu
Oracle

Zhe Wu received his PhD in computer science from the University of Illinois at Urbana-Champaign in 2001. He received his BE from the Special Class for Gifted Young, University of Science & Technology of China in 1996. He is currently a Consultant Member of Technical Staff working on semantic technologies in New England Development Center, Oracle. As an Oracle representative, he participates the W3C OWL (OWL 2) working group. And he served on UDDI standard specification technical committee from August 2003 to September 2005. His work and research interests are in Semantic Web technologies, logical inferencing, database, web services, nonlinear optimization, computer security, and computer networks