Monthly Archives: February 2011

Thomas Thurner

Vienna Semantic Web Meetup – the next season

by , Category: Corporate Semantic Web, Enterprise 2.0, Internet & Media, Linked Data & Open Data, Mashups & Web services, Open Government Data

Started mid 2009, Vienna Semantic Web Meetup (VSWM) goes now in it’s third year. Hosted by various partners, from media to culture and from corporate to academic, this regular gathering now counts over 200 members. As it is a good tradition at VSWM, people from abroad are visiting by, giving input and new insights. Also the next season of VSWM will bring this mixture of international connection and informal meeting in putting two upcoming topics onto the agenda.

Digital Identity on the Semantic Web
Thursday, April 7, 2011

While recent developments in ICT make it easier for companies and consumers to reach each other, they can also scatter your personal information more widely, making life easier for criminals. On the other hand public institutions and government agencies are collecting personal data too. So personal data is processed without the consensus (or even the knowledge) of the respective citizen. As we know, leaks in this field may unleash sensible personal data as well. The misuse of personal data can be restricted – this is a challenge to both, the technological and the juridical domain. This meetup takes a look on how Semantic Web Technologies can take over its responsibility in this emerging field.

  • Christof Tschohl (BIM)
    Ludwig Boltzmann Institute for Human Rights
  • Mischa Tuffield (Garlik)
    A Standards-based, Open and Privacy-aware Social Web (W3C)

>> read more, and register for free

Portals, Apps and Visualizations for Open Government Data
Wednesday, June 15, 2011

Picking up Keith Andrews suggestion, this is a MeetUp focusing on tools, services and projects dealing with Visualization, Apps-creation and Portals/Catalogs for Open [Government] Data. As this MeetUp is on the eve of Austrians first Open Government Data – Conference (OGD2011) we expect to meet experts ans enthusiasts from Austria and abroad.

  • Keith Andrews (IICM)
    Institute for Information Processing and Computer Supported New Media at Graz University of Technology
  • Andreas Blumauer (SWC)
    Storing, searching, serving Open Government Data – getting an overview on the growing market for open data solutions

>> read more, and register for free



Thomas Schandl

Transforming spreadsheets into SKOS with Google Refine

by , Category: Tools & Software, Vocabularies & Languages

Looking for high quality enterprise vocabularies we recently turned our attention to the Global Industry Classification Standard (GICS), which is an industry taxonomy designed to categorize any private company. It was developed by Morgan Stanley Capital International and Standard & Poor’s and is mainly used by the global financial community to aid in the investment research process.

It is available for download as .xls spreadsheet files in several languages. Of course it would be much better to have this valuable taxonomy in a standard and machine-readable format. The Simple Knowledge Organization System SKOS is a perfect fit for a taxonomy like GICS. But how to turn a spreadsheet into SKOS with minimal manual effort?

I chose to try Google Refine for this task, as recently a promising RDF extension had been released by DERI‘s Fadi Maali and Richard Cyganiak.

Google Refine is “a power tool for working with messy data, cleaning it up, transforming it from one format into another, extending it with web services, and linking it to databases”. Previously it was known as Freebase Gridworks which is now further developed by Google since its acquisition of Metaweb.

Refine

Google Refine UI

Refine is a very useful tool to filter and consequently transform rows, colums and cells according to customizable patterns.

After applying all necessary transformations to the spreadsheet one can edit the “RDF Skeleton”, where the columns can be mapped to literals, RDF properties and RDF classes (which can be imported from their namespaces).

RDF Sekeleton

Editing the RDF Sekeleton

Once you got your valid SKOS model ready you can export it in RDF/XML or Turtle format. Then you may want to load it into an ontology editor like Protégé or a thesaurus management tool like PoolParty in order to build upon it or connect it to other knowledge models. With PoolParty the GICS taxonomy can also be utilized to tag and categorize documents, provide semantic search and facetted navigation and it can be published as Linked Data without further effort.

GICS in PoolParty screenshot

GICS loaded in PoolParty

Working with Refine and its RDF extension was easy and fun. It’s even possible to isolate and save the transformation steps done with Refine, so one can re-apply them on similar structured spreadsheets. This came in very handy as GICS is published in nine languages and as many separate, identically structured spreadsheets.

Thomas Schandl

Drupal and the Semantic Web – Interview with Stéphane Corlosquet

by , Category: Linked Data & Open Data, Tools & Software

Stéphane Corlosquet has been the main driving force in incorporating Semantic Web capabilities into Drupal. In the recent release of Drupal 7, Semantic Web technologies became part of the core of this popular CMS, which is used to power at least 1% of all the world’s web sites.

Drupal is the leading CMS when it comes to implementing Semantic Web standards. What are the reasons for this, what makes Drupal such a good fit for Semantic Web technologies?

Historically, Drupal is known to be web standard compliant. It supported the RDF-based aggregation format known as RSS 1.0 as early as in 2001, which was later upgraded to RSS 2.0. The Drupal community prides itself in valid HTML code, not only for the code generated by Drupal, but also by taking the extra step of automatically fixing faulty HTML entered by its users. Drupal has been using XHTML since its version 4.0 in 2002. The next logical step beyond XHTML was to add a layer of semantics with the RDFa standard, a W3C recommendation published in 2008.

There are definitely many reasons that contributed to the addition of RDFa into Drupal 7. The first comes from the Drupal project lead, Dries Buytaert, who is passionate about the web and open source. Secondly, the growing Drupal community is very web savvy and includes many experts from different backgrounds in accessilibity, CSS, HTML, security etc. As a result, every release of Drupal includes many latest standards. The community meets twice a year at conferences (DrupalCons), thes events play a great role in hashing out what technologies or designs will be incorporated into the next version of Drupal. Because of the flexibility of its internal architecture, Drupal is able to keep up with the latest web standards. Content in Drupal is very structured and provides site administrators with a user interface to build the site structure they want, using entity types, content types, fields and taxonomies for categorization. When it comes to other CMSs, Joomla!’s community appears to be more fragmented with a core software that is not as extensible as Drupal and WordPress is more of a blogging platform, so turning it into a full blown CMS can be challenging. Both WordPress and Joomla! are in fact adapting the concept of Drupal’s Content Construction Kit (CCK) to their software but they have not yet reached the same level of maturity as Drupal.

A common objection to the adoption of Semantic Web technologies is that the learning curve is steep and that it is too complicated for many web developers to get into it. How can Drupal 7 change that? Which features accessible for the average web site operator will it offer?

Semantic Web technologies don’t have to be complicated when applied to simple use cases! We purposely chose only of a subset of semantic web technologies to integrate into the core of Drupal, keeping the learning curve for the Drupal developers and users as low as possible. The main technology is RDFa which includes the notions of vocabularies (a schema, or collection of attributes) as well as Compact URIs (CURIEs) which make the authoring of RDFa easier. In fact, some web developers might have come across these notions before when working with Dublin Core in the meta tags as such dc:title or dc:date.

Which benefits will web site owners get when they switch to a semantics enabled Drupal 7?

Google and Bing increasingly rely on machine-readable structured data from the websites that they crawl. The design of Drupal 7 embeds semantic meta data that makes machine-to-machine (M2M) search native for a Drupal 7 website. RDFa can add value by giving search engines more details such as the latitude and longitude of a venue for display on a map; or providing the ISO date format for localization and proper display in the search results for different countries.

What are your hopes regarding the development of other applications that either provide or consume data from D7 sites? Which improvements of standards, best practices or (lightweight) ontologies in the Semantic Web community would you like to see?

Services like Sig.ma are already able to collect semantic data from different sources and display it in new ways in the form of mash-ups. Eventually, these services that consume semantic data will not be just Drupal specific, as more platforms jump on the semantic web band wagon. What I hope to see as improvements or best practices in the future are more well-maintained vocabularies. Many of the existing vocabularies are over engineered, some fail to de-reference properly. Their is also some work to be done in order to improve the tooling made available to web developers as well as introducing the simple concepts of Linked Data to web developers via easy to read documentation.

Thank you for this interview, Stéphane!