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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
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<li class="current">Semantic Web</li>
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<h1 class="title">
<img src="/2008/site/images/theme-web-semantics" alt="" />Semantic Web</h1>
<ul class="w3c_toc"><li class="toc_prefix">On this page → </li><li>
<a href="#w3c_overview">technology topics</a>
<span class="bullet">•</span>
</li><li>
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<div class="intro">
<p>In addition to the classic “Web of documents” W3C is helping to build
a technology stack to support a “Web of data,” the sort of data you find in databases. The ultimate goal of the Web of data is to enable computers to do more useful work and to develop systems that can support trusted interactions over the network. The term “Semantic Web” refers to W3C’s vision of the Web of linked data. Semantic Web technologies enable people to create data stores on the Web, build vocabularies, and write rules for handling data. Linked data are empowered by technologies such as RDF, SPARQL, OWL, and SKOS.</p>
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<h2 class="w3c_topic">
<a href="/standards/semanticweb/data">Linked Data <img src="/2008/site/images/header-link" alt="Header link" width="13" height="13" class="header-link" />
</a>
</h2>
<p class="tPadding0">
The Semantic Web is a Web of data — of dates and titles
and part numbers and chemical properties and any other data one
might conceive of. RDF provides the foundation for publishing
and linking your data. Various technologies allow you to
embed data in documents (RDFa, GRDDL) or expose what you have
in SQL databases, or make it available as RDF files.
</p>
</div>
<div class="unit size1on3">
<h2 class="w3c_topic">
<a href="/standards/semanticweb/ontology">Vocabularies <img src="/2008/site/images/header-link" alt="Header link" width="13" height="13" class="header-link" />
</a>
</h2>
<p class="tPadding0">
At times it may be important or valuable to organize data.
Using OWL (to build vocabularies, or “ontologies”) and SKOS (for designing
knowledge organization systems) it is possible to
enrich data with additional meaning, which allows more people
(and more machines) to do more with the data.
</p>
</div>
<div class="unit size1on3 lastUnit">
<h2 class="w3c_topic">
<a href="/standards/semanticweb/query">Query <img src="/2008/site/images/header-link" alt="Header link" width="13" height="13" class="header-link" />
</a>
</h2>
<p class="tPadding0">
Query languages go hand-in-hand with databases.
If the Semantic Web is viewed as a global database, then
it is easy to understand why one would need a query language
for that data. SPARQL is the query language for the
Semantic Web.
</p>
</div>
</div>
<div class="line">
<div class="unit size1on3">
<h2 class="w3c_topic">
<a href="/standards/semanticweb/inference">Inference <img src="/2008/site/images/header-link" alt="Header link" width="13" height="13" class="header-link" />
</a>
</h2>
<p class="tPadding0">
Near the top of the Semantic Web stack one finds inference
— reasoning over data through rules. W3C work on rules,
primarily through RIF and OWL, is
focused on translating between rule languages and
exchanging rules among different systems.
</p>
</div>
<div class="unit size1on3">
<h2 class="w3c_topic">
<a href="/standards/semanticweb/applications">Vertical Applications <img src="/2008/site/images/header-link" alt="Header link" width="13" height="13" class="header-link" />
</a>
</h2>
<p class="tPadding0">
W3C is working with different industries — for example in
Health Care and Life Sciences, eGovernment, and Energy — to improve collaboration,
research and development, and innovation adoption through
Semantic Web technology. For instance, by aiding
decision-making in clinical research, Semantic Web
technologies will bridge many forms of biological and
medical information across institutions.
</p>
</div>
</div>
</div>
<div class="line">
<div id="recentnews" class="hierarchy hentry_list">
<h2 id="recent">News
<a title="Subscribe to News" href="http://www.w3.org/standards/semanticweb/news.xml" class="feedlink">
<img width="30" height="30" alt="Atom" src="/2008/site/images/icons/atom30" />
</a></h2>
<div class="hentry expand_block">
<div class="headline">
<h3 class="tPadding0 bPadding0 entry-title">
<span class="expand_section">
<a class="uri url" href="http://www.w3.org/blog/SW/2012/01/12/drafts-published-by-the-w3c-html-data-task-force-html-data-guide-and-microdata-to-rdf-transform/">
Drafts Published by the W3C HTML Data Task Force: HTML Data Guide
and Microdata to RDF transform</a>
</span>
</h3>
<p class="date">
<abbr class="published" title="2012-01-12">12
January 2012</abbr>
</p>
<p class="author vcard">from
<a class="fn org url" href="http://www.w3.org/blog/SW">Semantic Web
Activity News</a></p>
</div>
<div class="expand_description entry-content"><p>The
<a href="http://www.w3.org/wiki/Html-data-tf">HTML Data Task
Force</a> of the
<a href="http://www.w3.org/2001/sw/interest/">W3C Semantic Web
Interest Group</a>has published two documents today:</p><ul class="show_items">
<li>The
<a href="http://www.w3.org/TR/2012/WD-html-data-guide-20120112/">
HTML Data Guide</a>aims to help publishers and consumers of HTML
data. With several syntaxes (microformats, microdata, RDFa) and
vocabularies (schema.org, Dublin Core, microformat vocabularies,
etc.) to choose from, it provides guidance on deciding what to
choose in a way that meets the publisher’s or consumer’s
needs.</li>
<li>The
<a href="http://www.w3.org/TR/2012/WD-microdata-rdf-20120112/">
Microdata to RDF</a>describes processing rules that may be used to
extract RDF from an HTML document containing microdata.</li>
</ul><p>Both documents are Working Drafts, with the goal of publishing a
final version as Interest Group Notes. Comments and feedbacks are
welcome; please send them to the
<a href="mailto:public-html-data-tf@w3.org">
public-html-data-tf@w3.org</a>mailing list.</p></div>
</div>
<div class="hentry closed expand_block">
<div class="headline">
<h3 class="tPadding0 bPadding0 entry-title">
<span class="expand_section">
<a class="uri url" href="http://www.w3.org/blog/SW/2012/01/11/feedback-welcome-an-overview-of-the-provenance-prov-family-of-specs/">
Feedback Welcome: An Overview of the Provenance (PROV) family of
specs</a>
</span>
</h3>
<p class="date">
<abbr class="published" title="2012-01-11">11
January 2012</abbr>
</p>
<p class="author vcard">from
<a class="fn org url" href="http://www.w3.org/blog/SW">Semantic Web
Activity News</a></p>
</div>
<div class="expand_description entry-content"><p>Knowing how, where, when and why content was produced is an
important part of making a trustworthy web. However, it is often
difficult to interchange this provenance information between
systems. For example, it’s often difficult to locate or find
provenance information for a web page. Even if the provenance
information is located, it is often only available as text or if it
is available in a structured way it does not use a common
terminology — making it difficult to create software that can
leverage this information.</p><p>The
<a href="http://www.w3.org/2011/prov/wiki/Main_Page">Provenance
Working Group</a>was charted to help address these limitations. The
group has been working diligently to create a family of
specifications (called PROV) that allow for the interchange of
provenance. The group is looking for your feedback. This post
provides an overview of the various working drafts that have been
published and should help you find your way around.</p><p>The set of specs at this point addresses two aspects of
provenance interoperability introduced above:</p><ul class="show_items">
<li>provenance access</li>
<li>provenance representation</li>
</ul><p>
<a href="http://www.w3.org/TR/prov-aq/">PROV-AQ: Provenance Access
and Query</a>addresses how to both make available and retrieve
provenance information for Web resources. The document specifies
how to use existing Web technologies such as HTTP, link headers,
and SPARQL to accomplish this. Where possible the specification
attempts to be agnostic the format of the provenance being
accessed.</p><p>Once some provenance is obtained, it is important for the
information to be understandable in a machine interpretable
fashion. The Working Group has defined a data model (
<a href="http://www.w3.org/TR/prov-dm/">PROV-DM</a> ) that provides
facilities for representing the entities, people and activities
involved in producing a piece of data or thing in the world. The
data model is domain-agnostic and has well defined extensibility
points. Importantly, the data model has a corresponding OWL
ontology (
<a href="http://www.w3.org/TR/prov-o/">PROV-O</a>) that encodes the
PROV-DM. PROV-O is envisioned to specify the serialization for
exchanging provenance information.</p><p>To help orient users of PROV-O and PROV-DM, the working group
has developed a primer (
<a href="http://www.w3.org/TR/prov-primer/">PROV-Primer</a>) that
introduces the core constructs of the data model and provides
examples using PROV-O. It is recommended that users and reviewers
of the specification begin with the primer before moving to the
ontology or data model.</p><p>The group is looking for feedback of all types: Would you expose
provenance using PROV-AQ? Can you represent your provenance
information using the PROV-O data model? Does PROV-O integrate well
with your Linked Data or other Semantic Web infrastructure?</p><p>Let us know what you think.</p><p>The PROV family of specifications:</p><ul class="show_items">
<li>prov-aq:
<a href="http://www.w3.org/TR/prov-aq/">
http://www.w3.org/TR/prov-aq/</a></li>
<li>prov-dm:
<a href="http://www.w3.org/TR/prov-dm/">
http://www.w3.org/TR/prov-dm/</a></li>
<li>prov-o:
<a href="http://www.w3.org/TR/prov-o/">
http://www.w3.org/TR/prov-o/</a></li>
<li>prov-primer:
<a href="http://www.w3.org/TR/prov-primer/">
http://www.w3.org/TR/prov-primer/</a></li>
</ul><div class="lMargin"><p>Paul Groth and Luc Moreau on behalf of the PROV-WG</p></div></div>
</div>
<div class="hentry closed expand_block">
<div class="headline">
<h3 class="tPadding0 bPadding0 entry-title">
<span class="expand_section">
<a class="uri url" href="http://www.w3.org/blog/SW/2012/01/10/provenance-access-and-query-and-provenance-primer-documents-published/">
Provenance Access and Query and Provenance Primer Documents
published</a>
</span>
</h3>
<p class="date">
<abbr class="published" title="2012-01-10">10
January 2012</abbr>
</p>
<p class="author vcard">from
<a class="fn org url" href="http://www.w3.org/blog/SW">Semantic Web
Activity News</a></p>
</div>
<div class="expand_description entry-content"><p>The
<a href="http://www.w3.org/2011/prov">W3C Provenance Working
Group</a>has published two new documents:</p><ul class="show_items">
<li>The
<a href="http://www.w3.org/TR/2012/WD-prov-aq-20120110/">
“Provenance Access and Query”</a> document specifies how to use
standard Web protocols, including HTTP, to obtain information about
the
<a class="zem_slink" title="Provenance" href="http://en.wikipedia.org/wiki/Provenance">provenance</a>of Web
resources.</li>
<li>The
<a href="http://www.w3.org/TR/2012/WD-prov-primer-20120110/">
“Provenance Primer”</a>provides an intuitive introduction and guide
to the PROV data model for provenance</li>
</ul><p>Both documents are First Public Working Drafts; feedbacks and
comments are welcome! Please, use the
<a href="mailto:public-prov-comments@w3.org">
<code>public-prov-comments@w3.org</code>
</a>mailing list to provide your comments.</p><div class="zemanta-pixie lMargin"><p>
<img class="zemanta-pixie-img" src="http://img.zemanta.com/pixy.gif?x-id=797d5232-6df8-43b7-837d-fb27bad4b58f" alt="" />
</p></div></div>
</div>
<div class="hentry closed expand_block">
<div class="headline">
<h3 class="tPadding0 bPadding0 entry-title">
<span class="expand_section">
<a class="uri url" href="http://www.w3.org/blog/SW/2012/01/06/publication-of-the-sparql-1-1-2nd-last-call-working-drafts/">
Publication of the SPARQL 1.1 2nd Last Call Working Drafts</a>
</span>
</h3>
<p class="date">
<abbr class="published" title="2012-01-06">06
January 2012</abbr>
</p>
<p class="author vcard">from
<a class="fn org url" href="http://www.w3.org/blog/SW">Semantic Web
Activity News</a></p>
</div>
<div class="expand_description entry-content"><p>The W3C
<a href="http://www.w3.org/2009/sparql/wiki/Main_Page">SPARQL
Working Group</a>has published the (second) Last Call Working
Drafts of the following SPARQL 1.1 documents:</p><ul class="show_items">
<li>
<a href="http://www.w3.org/TR/2012/WD-sparql11-update-20120105/">
SPARQL 1.1 Update</a>defines an update language for RDF
graphs.</li>
<li>
<a href="http://www.w3.org/TR/2012/WD-sparql11-service-description-20120105/">
SPARQL 1.1 Service Description</a>defines a vocabulary and
discovery mechanism for describing the capabilities of a SPARQL
endpoint.</li>
<li>
<a href="http://www.w3.org/TR/2012/WD-sparql11-query-20120105/">
SPARQL 1.1 Query Language</a>adds support for aggregates,
subqueries, projected expressions, and negation to the SPARQL query
language.</li>
<li>
<a href="http://www.w3.org/TR/2012/WD-sparql11-protocol-20120105/">
SPARQL 1.1 Protocol</a>describes a means for conveying SPARQL
queries and updates to a SPARQL processing service and returning
the results via HTTP to the entity that requested them.</li>
<li>
<a href="http://www.w3.org/TR/2012/WD-sparql11-entailment-20120105/">
SPARQL 1.1 Entailment Regimes</a>defines conditions under which
SPARQL queries can be used with entailment regimes such as RDF, RDF
Schema, OWL, or RIF.</li>
</ul><p>Review comments are welcome through 6 February; please use the
dedicated mailing list:
<a href="mailto:public-sparql-dev@w3.org">
public-sparql-dev@w3.org</a>.</p></div>
</div>
<div class="hentry closed expand_block">
<div class="headline">
<h3 class="tPadding0 bPadding0 entry-title">
<span class="expand_section">
<a class="uri url" href="http://ivan-herman.name/2011/12/16/where-we-are-with-rdfa-1-1/">
Where we are with RDFa 1.1?</a>
</span>
</h3>
<p class="date">
<abbr class="published" title="2011-12-16">16
December 2011</abbr>
</p>
<p class="author vcard">from
<a class="fn org url" href="http://ivan-herman.name">Ivan’s private
site » Work Related</a></p>
</div>
<div class="expand_description entry-content"><div class="mceTemp lMargin"><div class="wp-caption alignright lMargin"><p>
<a href="http://commons.wikipedia.org/wiki/File:Rdface.gif">
<img class="zemanta-img-inserted zemanta-img-configured" title="English: RDFa Content Editor" src="http://upload.wikimedia.org/wikipedia/commons/4/48/Rdface.gif" alt="English: RDFa Content Editor" width="120" height="120" />
</a>
</p><p class="wp-caption-text">Image via Wikipedia</p></div></div><p>There has been a flurry of activities around RDFa 1.1 in the
past few months. Although a number of blogs and news items have
been published on the changes, all those have become “officialized”
only the past few days with the
<a href="http://www.w3.org/blog/SW/2011/12/16/new-versions-of-rdfa-core-1-1-and-the-xhtmlrdfa-1-1-drafts/">
publication of the latest drafts</a> , as well as with the
<a href="http://www.w3.org/blog/SW/2011/12/09/rdfa-lite-1-1-draft-published-rdfa-1-1-primer-updated/">
publication of RDFa 1.1 Lite</a>. It may be worth looking back at
the past few months to have a clearer idea on what happened. I make
references to a number of other blogs that were published in the
past few months; the interested readers should consult those for
details.</p><p>The latest official drafts for RDFa 1.1 were published in Spring
2011. However, lot has happened since. First of all, the
<a href="http://www.w3.org/2010/02/rdfa/wiki/Main_Page">RDFWA
Working Group</a> , working on this specification, has received a
significant amount of comments. Some of those were rooted in
implementations and the difficulties encountered therein; some came
from potential authors who asked for further simplifications. Also,
the announcement of
<a href="http://schema.org">schema.org</a> had an important effect:
indeed, this initiative drew attention on the importance of
structured data in Web pages, which also raised further questions
on the usability of RDFa for that usage pattern This came to the
fore even more forcefully at the
<a href="http://www.w3.org/QA/2011/09/impressions_on_the_schemaorg_w.html">
workshop organized by the stakeholders of schema.org</a> in Mountain
View. A new
<a href="http://www.w3.org/wiki/Html-data-tf">task force on the
relationships of RDFa and microdata</a>has been set up at W3C;
beyond looking at the relationship of these two syntaxes, that task
force also raised a number of issues on RDFa 1.1. These issues have
been, by and large, accepted and handled by the Working Group (and
reflected in the new drafts).</p><p>What does this mean for the new drafts? The bottom line: there
have been some fundamental changes in RDFa 1.1. For example,
profiles, introduced in earlier releases of RDFa 1.1, have been
removed due to implementation challenges; however, management of
vocabularies have acquired an
<em>optional</em>feature that helps vocabulary authors to “bind”
their vocabularies to other vocabularies, without introducing an
extra burden on authors (see
<a href="http://www.w3.org/blog/SW/2011/09/19/recent-changes-in-rdfa-1-1/">
another blog</a> for more details). Another long-standing issue was
whether RDFa should include a syntax for ordered lists; this has
been done now (see the
<a href="http://www.w3.org/blog/SW/2011/09/19/recent-changes-in-rdfa-1-1/">
same blog</a>for further details).</p><p>A more recent important change concerns the usage of
<code>@property</code>and
<code>@rel</code>. Although usage of these attributes for RDF savy
authors was never a real problem (the former is for the creation of
literal objects, whereas the latter is for URI references), they
have proven to be a major obstacle for ‘lambda’ HTML authors. This
issue came up quite forcefully at the schema.org workshop in
Mountain View, too. After a long technical discussion in the group,
the new version reduces the usage difference between the two
significantly. Essentially, if, on the same element,
<code>@property</code>is present together with, say,
<code>@href</code>or
<code>@resource</code>, and
<code>@rel</code>or
<code>@rev</code>is
<em>not</em>present, a URI reference is generated as an object of
the triple. I.e., when used on a, say,
<code><link></code>or
<code><a></code>element,
<code>@property</code>  behaves exactly like
<code>@rel</code>. It turns out that this usage pattern is so
widespread that it covers most of the important use cases for
authors. The new version of the
<a href="http://www.w3.org/TR/rdfa-primer/">RDFa 1.1 Primer</a> (as
well as the
<a href="http://www.w3.org/TR/2011/WD-rdfa-core-20111215/">RDFa 1.1
Core</a>, actually) has a number of examples that show these. There
are also some other changes related to the behaviour of
<code>@typeof</code>in relations to
<code>@property</code>; please consult the specification for
these.</p><p>The publication of
<a href="http://www.w3.org/TR/rdfa-lite/">RDFa 1.1 Lite</a> was also
a very important step. This defines a “sub-set” of the RDFa
attributes that can serve as a guideline for HTML authors to
express simple structured data in HTML without bothering about more
complex features. This is the subset of RDFa that
<a href="http://blog.schema.org/2011/11/using-rdfa-11-lite-with-schemaorg.html">
schema.org will “accept”,</a>   as an alternative to the
<a href="http://dev.w3.org/html5/md/">microdata</a> , as a possible
syntax for schema.org vocabularies. (There are some examples on how
some schema.org example look like in RDFa 1.1 Lite on a
<a href="http://www.w3.org/QA/2011/11/schemaorg_and_rdfa_11_lite_how.html">
different blog</a> .) In some sense, RDFa 1.1 Lite can be considered
like the equivalent of microdata, except that it leaves the door
open for more complex vocabulary usage, mixture with different
vocabularies, etc. (The
<a href="http://www.w3.org/wiki/Html-data-tf">HTML Task
Force</a>will publish soon a more detailed comparison of the
different syntaxes.)</p><p>So here is, roughly, where we are today. The recent publications
by the W3C RDFWA Working Group have, as I said, ”officialized” all
the changes that were discussed since spring. The group decided not
to publish a Last Call Working Draft, because the last few weeks’
of work on the
<a href="http://www.w3.org/wiki/Html-data-tf">HTML Task
Force</a>may reveal some new requirements; if not, the last round
of publications will follow soon.</p><p>And what about implementations? Well,
<a href="http://www.w3.org/2007/08/pyRdfa/Shadow.html">my “shadow”
implementation of the RDFa distiller</a> (which also includes a
separate “
<a href="http://www.w3.org/2007/08/pyRdfa/Validator.html">
validator</a> ” service) incorporates all the latest changes. I also
added a new feature a few weeks ago, namely the possibility to
<a href="http://www.w3.org/QA/2011/11/rdfa_11_meets_json-ld_in_the_d.html">
serialize the output in JSON-LD</a> (although this has become
outdated a few days ago, due to some
<a href="http://json-ld.org/minutes/2011-12-13/">changes in
JSON-LD</a> …). I am not sure of the exact status of Gregg Kellogg’s
<a href="http://rdf.greggkellogg.net/distiller">RDF Distiller</a>,
but, knowing him, it is either already in line with the latest
drafts or it is only a matter of a few days to be so. And there are
surely more around that I do not know about.</p><p>This last series of publications have provided a nice closure
for a busy RDFa year. I guess the only thing now is to wish
everyone a Merry Christmas, a peaceful and happy Hanukkah, or other
festivities you honor at this time of the year.  In any case,
a very happy New Year!</p><div class="zemanta-pixie lMargin"><p>
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<br />Filed under:
<a href="http://ivan-herman.name/category/work-related/code/python/">
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<a href="http://ivan-herman.name/category/work-related/semantic-web/">
Semantic Web</a> ,
<a href="http://ivan-herman.name/category/work-related/">Work
Related</a> Tagged:
<a href="http://ivan-herman.name/tag/html/">HTML</a> ,
<a href="http://ivan-herman.name/tag/html5/">HTML5</a> ,
<a href="http://ivan-herman.name/tag/json/">JSON</a> ,
<a href="http://ivan-herman.name/tag/rdfa/">RDFa</a> ,
<a href="http://ivan-herman.name/tag/rdfa-1-1-lite/">RDFa 1.1
Lite</a> ,
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Resource Description Framework</a> ,
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<div class="hentry closed expand_block">
<div class="headline">
<h3 class="tPadding0 bPadding0 entry-title">
<span class="expand_section">
<a class="uri url" href="http://www.w3.org/blog/SW/2011/12/16/new-versions-of-rdfa-core-1-1-and-the-xhtmlrdfa-1-1-drafts/">
New Versions of RDFa Core 1.1 and the XHTML+RDFa 1.1 Drafts</a>
</span>
</h3>
<p class="date">
<abbr class="published" title="2011-12-16">16
December 2011</abbr>
</p>
<p class="author vcard">from
<a class="fn org url" href="http://www.w3.org/blog/SW">Semantic Web
Activity News</a></p>
</div>
<div class="expand_description entry-content"><p>The
<a href="http://www.w3.org/2010/02/rdfa/">RDF Web Applications
Working Group</a> has published a Working Draft of
<a href="http://www.w3.org/TR/2011/WD-rdfa-core-20111215/">RDFa
Core 1.1</a> , a specification for attributes to express structured
data in any markup language. The group also published an update to
<a href="http://www.w3.org/TR/2011/WD-xhtml-rdfa-20111215/">
XHTML+RDFa 1.1</a>, a Host Language for RDFa Core 1.1. This
document is intended for authors who want to create XHTML Family
documents that embed rich semantic markup.</p><div class="zemanta-pixie lMargin"><p>
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<img class="zemanta-pixie-img" src="http://img.zemanta.com/zemified_e.png?x-id=5050aaea-e7e5-4d34-a26e-22f990f98f1c" alt="Enhanced by Zemanta" />
</a>
</p></div></div>
</div>
<div class="hentry closed expand_block">
<div class="headline">
<h3 class="tPadding0 bPadding0 entry-title">
<span class="expand_section">
<a class="uri url" href="http://www.w3.org/blog/SW/2011/12/16/new-version-of-the-prov-data-model-draft/">
New Version of the PROV Data Model Draft</a>
</span>
</h3>
<p class="date">
<abbr class="published" title="2011-12-16">16
December 2011</abbr>
</p>
<p class="author vcard">from
<a class="fn org url" href="http://www.w3.org/blog/SW">Semantic Web
Activity News</a></p>
</div>
<div class="expand_description entry-content"><p>The
<a href="http://www.w3.org/2011/prov/">Provenance Working
Group</a> has published a new Working Draft of
<a href="http://www.w3.org/TR/2011/WD-prov-dm-20111215/">The PROV
Data Model and Abstract Syntax Notation</a> . Provenance of
information is crucial in deciding whether information is to be
trusted, how it should be integrated with other diverse information
sources, and how to give credit to its originators when reusing it.
In an open and inclusive environment such as the Web, users find
information that is often contradictory or questionable:
<a class="zem_slink" title="Provenance" href="http://en.wikipedia.org/wiki/Provenance">provenance</a> can
help those users to make trust judgments. PROV-DM is a
<a class="zem_slink" title="Data model" href="http://en.wikipedia.org/wiki/Data_model">data model</a>for
provenance for building representations of the entities, people and
activities involved in producing a piece of data or thing in the
world.</p><div class="zemanta-pixie lMargin"><p>
<a class="zemanta-pixie-a" title="Enhanced by Zemanta" href="http://www.zemanta.com/">
<img class="zemanta-pixie-img" src="http://img.zemanta.com/zemified_e.png?x-id=ae5feb7d-3daf-47b8-a892-ef1162962794" alt="Enhanced by Zemanta" />
</a>
</p></div></div>
</div>
<div class="hentry closed expand_block">
<div class="headline">
<h3 class="tPadding0 bPadding0 entry-title">
<span class="expand_section">
<a class="uri url" href="http://www.w3.org/blog/SW/2011/12/13/first-public-working-draft-of-the-prov-ontology-published/">
First Public Working Draft of the PROV Ontology published</a>
</span>
</h3>
<p class="date">
<abbr class="published" title="2011-12-13">13
December 2011</abbr>
</p>
<p class="author vcard">from
<a class="fn org url" href="http://www.w3.org/blog/SW">Semantic Web
Activity News</a></p>
</div>
<div class="expand_description entry-content"><p>The W3C
<a href="http://www.w3.org/2011/prov/">Provenance Working
Group</a> has published the First Public Working Draft of
<a href="http://www.w3.org/TR/2011/WD-prov-o-20111213/">The PROV
Ontology: Model and Formal Semantics</a> . The PROV Ontology (also
known as PROV-O) encodes the
<a href="http://www.w3.org/TR/2011/WD-prov-dm-20111018/">PROV Data
Model</a>in the OWL2 Web Ontology Language (OWL2). The PROV
ontology consists of a set of classes, properties, and restrictions
that can be used to represent provenance information. The PROV
ontology can also be specialized to create new classes and
properties for modeling provenance information specific to
different domain applications. The PROV ontology supports a set of
entailments based on OWL2 formal semantics and provenance specific
inference rules. The PROV ontology is available for download as a
separate OWL2 document.</p><div class="zemanta-pixie lMargin"><p>
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<div class="headline">
<h3 class="tPadding0 bPadding0 entry-title">
<span class="expand_section">
<a class="uri url" href="http://www.w3.org/blog/International/2011/12/09/w3c-workshop-call-for-participation-the-multilingual-web-%e2%80%93-the-way-ahead/">
W3C Workshop, Call for Participation: The Multilingual Web – The
Way Ahead</a>
</span>
</h3>
<p class="date">
<abbr class="published" title="2011-12-09">09
December 2011</abbr>
</p>
<p class="author vcard">from
<a class="fn org url" href="http://www.w3.org/blog/International">
Internationalization Activity Blog » w3cSemanticWeb</a></p>
</div>
<div class="expand_description entry-content"><div class="lMargin"><p>
<img src="http://www.w3.org/International/multilingualweb/images/mlw-logo.png" alt=" " />
</p></div><p>
<strong>15 – 16 March 2012, Luxembourg</strong>. Co-located with
the European Commission’s Language Technology Showcase Days, and
hosted by the Directorate-General for Translation (DGT) of the
European Commission.</p><p>The
<a href="http://www.multilingualweb.eu/">MultilingualWeb
project</a>is looking at best practices and standards related to
all aspects of creating, localizing and deploying the Web
multilingually. The project aims to raise the visibility of
existing best practices and standards and identify gaps. The core
vehicle for this is a series of four events which are planned over
two years.</p><p>After three highly successful workshops in Madrid, Pisa, and
Limerick, this final workshop in the series will continue to
investigate currently available best practices and standards aimed
at helping content creators, localizers, tools developers, and
others meet the challenges of the multilingual Web.</p><p>Participation is free. We welcome participation from both
speakers and non-speaking attendees. For more information, see the
<a href="http://www.multilingualweb.eu/register">Call for
Participation</a></p></div>
</div>
<div class="hentry closed expand_block">
<div class="headline">
<h3 class="tPadding0 bPadding0 entry-title">
<span class="expand_section">
<a class="uri url" href="http://www.w3.org/blog/SW/2011/12/09/rdfa-lite-1-1-draft-published-rdfa-1-1-primer-updated/">
RDFa Lite 1.1 Draft Published; RDFa 1.1 Primer Updated</a>
</span>
</h3>
<p class="date">
<abbr class="published" title="2011-12-09">09
December 2011</abbr>
</p>
<p class="author vcard">from
<a class="fn org url" href="http://www.w3.org/blog/SW">Semantic Web
Activity News</a></p>
</div>
<div class="expand_description entry-content"><p>The
<a href="http://www.w3.org/2010/02/rdfa/">RDF Web Applications
Working Group</a> has published the First Public Working Draft for
<a href="http://www.w3.org/TR/rdfa-lite/">RDFa Lite 1.1</a> and an
updated Working Draft for the
<a href="http://www.w3.org/TR/rdfa-primer/">RDFa 1.1
Primer</a>.</p><p>One critique of RDFa is that is has too much functionality,
leaving first-time authors confused about the more advanced
features. RDFa Lite is a minimalist version of RDFa that helps
authors easily jump into the structured data world. The goal was to
outline a small subset of RDFa that will work for 80% of the Web
authors out there doing simple data markup.</p><p>The RDFa Primer is a more in-depth introduction to RDFa and all
of the structured data markup features that it provides.</p><div class="zemanta-pixie lMargin"><p>
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Talks and Appearances
<img src="/2008/site/images/header-link" alt="Header link" width="13" height="13" class="header-link" /></a></h2><ul class="vevent_list"><li class="vevent"><p class="date single"><span class="dtstart"><span class="year">2012</span><span class="mm-dd">-04-17</span></span> <span class="paren">(</span><span class="dd-mmm">17 APR</span><span class="paren">)</span></p><div class="info-wrap"><p class="summary">Open Data in Practice</p><p class="eventtitle"><a href="http://www.w3.org/2012/04/tuto-track.html" class="uri">W3C Tutorial Track, 21st International World Wide Web Conference (WWW2012)</a></p><p class="location">Lyon,
France</p></div></li></ul><p>See also the <a href="/Talks/">full list of W3C Talks and Appearances</a>.</p></div>
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