Step 1. Generate a thesaurus by using a linked data source like DBpedia

As recently reported SWC has developed a tool called SKOSsy which can be used to extract seed thesauri from DBpedia. In our example I will generate a knowledge model describing the domain of “digital photography“. This step took around 15 minutes.

Step 2. Load the thesaurus into PoolParty and improve it to your needs

After the seed thesaurus has been loaded into PoolParty Thesaurus Manager you have many possibilities to enhance the knowledge model further: Add more categories, synonyms, relations etc. In this example I use the seed-thesaurus without any further improvements. This step took approximately 2 minutes.

Step 3. Generate an automatic text extractor on top of your thesaurus

This step took a couple of seconds and ended up in having generated a fast and reliable text mining application on top of PoolParty Extractor, ready to be used to enrich your documents with data from the LOD cloud.

You can try it out here: PPX Live-Demo

To try the extractor on your own, please take a look at the image above which shows a proper configuration, you have to insert the following UUID in the form: d35d4ddb-adc3-4ea5-b027-deacac03e391

Since our example is all about ‘digital photography’, we recommend to use text samples (or some fragments) like these ones to test the quality of PPX based text analytics:

• Digital Camera Image Noise (Results as HTML, RDF/XML)
• Nikon D3S In-depth Review (Results as HTML, RDF/XML)
• Introduction to Shutter Speed in Digital Photography (Results as HTML, RDF/XML)
• Digital Camera Sensors (Results as HTML, RDF/XML)

Let us know what you think about this straight-forward approach and your opinion about the quality of the results. We believe that thesaurus based text mining is in many cases an alternative to some other approaches, especially if you want to to enrich your content with information from the upcoming web of data.

Of course we would be happy to generate other demos in the areas of your interest! Just get in contact with us by using our contact form.

Linked Open Data: The Essentials provides answers to the following key questions:

• What do the terms Open Data, Open Government Data and Linked Open Data actually mean, and what are the differences between them?
• What do I need to take into account in developing a LOD strategy?
• What does my organisation need to do technically in order to open up and publish its datasets?
• How can I make sure the data is accessible and digestible for others?
• How can I add value to my own data sets by consuming LOD from others?
• What can be learned existing best practices?
• What are the key potentials of sharing and consuming open datasets?

Read more about this publication and find out how to obtain a copy.

From September 6 – 8, 2010 we kicked off the LOD2 project in Leipzig / Germany. LOD2 is funded by the European Commission within the 7th Framework Programme (Grant Agreement No. 257943) consisting of 10 partners from 7 countries. Its main aim is to integrate and syndicate linked data with large-scale, existing applications and showcase the benefits in three application scenarios: 1) Media & Publishing, 2) Enterprise Data Management and 3) Open Government Data. The resulting tools, methods and data sets have the potential to change the Web as we know it today. (You can download the project flyer here.)

The first day was dedicated to the general introduction of the project partners which are Universität Leipzig (Germany), Centrum Wiskunde & Informatica (Netherlands), National University of Ireland in Galway (Ireland), Freie Universität Berlin (Germany), OpenLink Software (United Kingdom), Semantic Web Company (Austria), TenForce (Belgium), Exalead (France), Wolters Kluwer Deutschland (Germany) and Open Knowledge Foundation (United Kingdom). Below you see a picture of the kick off team.

During the morning of the second day a first introduction to the technical components took place. The picture below shows an abstraction of the LOD2 high level architecture.

Orri Erling and Hugh Williams from OpenLink introduced Virtuoso, which will be used as one of the storage technologies in the LOD2 stack. The second knowledge store technology will be MonetDB introduced by Peter Boncz from CWI. Both systems will also be used as a kind of benchmark laboratory for hosting and querying linked data.

Christian Bizer from FU Berlin talked about Silk and D2R. In combination they will be used to discover relationship and similarities between entities within different linked data sources – generally called identity resolution.

Giovanni Tummarello from DERI introduced Sindice and Sig.ma under the aspect of how to update, validate and reuse data that is available on the web and support the production of professional, collaboratively governed linked data especially for enterprise use. Beside that an important aspect will be how to handle the high amounts of generated data. So according to Giovanni scaling the infrastructure and the use of appropriate hardware will be central in bringing the Sindice index into enterprise stacks i.e. as an approach for lightweight data consolidation purposes.

Norman Heino from AKSW University of Leipzig introduced OntoWiki and Semantic Pingback. Ontowiki will be used at the interface layer for producing, annotating, browsing and querying linked data and presenting it to the enduser in various GUIs. Semantic Pingback’s aim is to interlink the Web 2.0 with the Semantic Web by backwards compatible RPCs (remote procedure calls). It detects new typed or untyped external links, manages the GET and POST commands and it takes care of server autodiscovery.

Andreas Blumauer from Semantic Web Company demonstrated PoolParty as a smart editor for metadata in enterprise stacks. Like Ontowiki PoolParty also addresses the interface level of LOD2 especially when it comes to generate, edit and link metadata to documents primarily based on SKOS. PoolParty deliberatelly uses Thesauri as a mapping layer to discover similarities of documents, generate tag recommendations for their annotation and publish used vocabularies as Linked Data.

In the afternoon we continued with individual breakout sessions to discuss work package interdependencies and start profiling the use cases and requirements eingineering in more detail.

The third day started with an introduction by Stefano Bertolo – the responsible scientific project officer from the EC side for the LOD2 project – who pointed out that the LOD2 project is an important one for the European Web of Data and the EC among others specially is interested in the Open Government Data use case of LOD2.

After this introduction talks of the 3 Use Cases were presented by A) Jonathan Gray (OKFN) about the Open Gov Data use case followd by B) Amar-Djalil MEZAOUR (Exalead) speaking about the Linked Business Data use case and C) Christian Dirschl (Wolters Kluwer) having a talk about the LOD in the publishing & media industry use case.

Central to the success of LOD2 will be a smart handling of all the integration issues which will come up in the course of the project. Here Tenforce, an integration specialist from Belgium, will have the lead. CEO Bastiaan Deblieck gave a detailed outlook on the methodologies  and he presented a nice and comprehensive overview how the integration issues will be approached from a SCRUM perspective.

After a presentation about LOD2 project dissemination, training and community building activities by Martin Kaltenböck (Semantic Web Company) there were serveral discussions going on until the successful kick off meeting was closed by project lead Sören Auer (Universität Leipzig) at 04.00pm of 08 September 2010.

Updated news information can be accessed on the LOD2 project website as well as on the LOD2project twitter stream (and on twitter using #lod2)…

Stay tuned!

The first day started off with a keynote by Richard Cyganiak form DERI Galway’s Linked Data Research Center. He talked about the technical challenges that have to be overcome to allow for more Linked Data applications over heterogenous RDF data. These challenges revolve around discovery of and access to Linked Data, identifier and schema reconciliation, data fusion, quality assessment, aggregation, analytics and mining.
As Richard pointed out, the good news is “that linked data makes it possible that different people do the different steps, e.g., the publisher can help doing the identifier reconciliation by publishing sameAs links, and 3rd parties can help with access by providing a single SPARQL store over multiple related but independent datasets.” Check out the transcript
or slides for Richard’s talk.

After this keynote participants presented their topics of interest in Lightning Talks and working groups formed, some of their outcomes can be found online:
One group worked on the topic of “Dataset Dynamics”. As data in Linked Data sets change, clients having some dependency on data need to be notified about these changes. You can read about their proposed solutions here.
Another group had a go at “Expert search and profiling on the Semantic Web”, their discussions are summarized in this blog post.
Andreas Langegger demonstrated XLWrap, which is a versatile RDF wrapper for spreadsheets. A lot of feature request from participants came up (see here), so he and others worked on this handy application.

On day 2 Leigh Dodds from Talis talked about “Rights Statements on the Web of Data” (slides and transcript). Leigh raised awareness for the issue that the majority of LOD sources do not have licensing information associated with their data. This of course conflicts with the proposed openness of Linked “Open” Data, as it is doubtful whether these sources can be used for commercial puropses.

The organizers from the universities of Linz and Vienna, Joanneum Research, Gnowsis, DERI Galway, STI Innsbruck and the Semantic Web Company would like to thank all participants for making the camp a success! As with VoCamps anyone can organize a Linked Data Camp, so we hope for more camps in 2010!

The challenge (Patron: Sir Tim Berners-Lee) is open to anyone interested in applying Semantic Web and Linked Data technologies. We envision submissions such as following:

• Applications of Linked Data tools and techniques such as for example Triplify, Virtuoso or D2RQ on custom Web applications and data sets exposing a large quantity and variety of content.
• Implementations of exporters and mappers from existing content repository formats (such as mbox mailing list archives, Bib Te X, XML-Schemes etc.) into RDF and Linked Data.
• Adoptions / configurations of Triplify for standard Web applications, such as for example Wikis, Weblogs, Webshops, Forums, Web-Gallery, ERP/CRM systems and Web-calendar software. You can find popular Web applications for example at Source Forge.
• Portings of the Triplify script into other Web application programming languages such as Python, Ruby, Perl, ASP. The Triplify script is very small (<300 lines of code) however, the port should be as compatible as possible with the current reference implementation but integrate well with the environment given by the programming language.
• Applications showcasing the benefits of Linked Data to end-users such as for information syndication, specialized search, browsing or augmentation of content.

Submissions should consist of a two page description in JUCS format of the application, accompanied by (a link to) the software source code and a link to an online demo. The descriptions should be submitted electronically via email to Michael Hausenblas with the subject Triplification Challenge Submission by May 30th, 2009.

He administrates the site LinkedData.org (on behalf of the Linked Data community), he is the creator of Revyu.com (“Review anything!”), which won him the 1st prize in the Semantic Web Challenge 2007, he was a co-organizer of the Linked Data on the Web Workshop at this year’s World Wide Web conference in Beijing, and he was an interviewee in my 12 seconds definitions mission @ TRIPLE-I – see his micro definition of Linked Data in the vid below. (To learn more about Tom and the different roles he fulfils, look here).

Tom Heath explains Linked Data TRIPLE-I 2008 on 12seconds.tv

His keynote was not so much an introduction to Linked Data (I should expect that a conference like TRIPLE-I/I-Semantics would typically attract people who at least have an idea of what Linked Data is about), but rather a confirmation that the Web of Data is no longer a fiction, but a fact. One of the often cited proofs is the growth of the LOD dataset cloud over the last year, as shown in the image below (clicky for biggy, visualization created by Richard Cyganiak).

At the same time – and this was accordingly acknowledged by a later presentation given by Wolfgang Halb which had been prepared collaboratively by Tom, Wolfgang, Michael Hausenblas and Yves Raimond – it’s not just the sheer number of triples on the web that counts. Over the course of one year, the efforts of the Linked Data community (who seek to populate the web with open data, data in RDF) generated 4 billion triples – but only 3 million interlinks.

Their paper was an attempt to measure the size of the Semantic Web based on interlinks. A brief excerpt from the conclusion:

We have identified two different types of datasets, namely single- point-of-access datasets (such as DBpedia), and distributed datasets (e.g. the FOAF-o-sphere). At least for the single-point-of-access datasets it seems that automatic interlinking yields a high number of semantic links, however of rather shallow quality. Our finding was that not only the number of triples is relevant, but also how the datasets both internally and externally are interlinked. Based on this observation we will further research into other types of Semantic Web data and propose a metric for gauging it, based on the quality and quantity of the semantic links. We expect similar mechanisms (for example regarding automatic interlinking) to take place on the Semantic Web.

Another point raised by Tom in his key note was the issue of trust: According to his research, there are five parameters that have an influence on whether we trust a source or recommendation on the web or not: experience , expertise, impartiality (we don’t trust a travel agent, because we can’t help but believe that she is mainly going to recommend the offer of her ‘favourite’ clients), affinity, and track record, with experience, expertise and affinity being the most important ones. A semantic people search engine Tom presented, Hoonoh.com (currently in alpha), thus allows to weight search results according to these three criteria.

Tom’s concluding statement emphasized that Linking Data makes sense not for the sake of it, but for the sake of being at the service of humans: “A web of machine-readable data is even more interesting from a human than from a machine perspective,” for instance in search engines like Hoonoh.com