Semantic Web Applications

Semantic Web Applications

IntroductionVlad Posea

vladposea@yahoo.com

• http://www.ted.com/talks/tim_berners_lee_on_the_next_web.html

On the next web

• Web 1.0 = a way to reframe the way we use information

• Overcome the need for systems to be interoperable in order for people to better access each others’ documents

• => TBL was frustrated – => he built a system to overcome that– Great idea – linking documents - hypertext

Which is the problem that still frustrates people and TBL?

• Turns out that there is still huge unlocked potential. There is still a huge frustration that people have because we haven't got data on the web as data.

• Which is the difference between document and data?– On the web we have links between documents

not between data sets

Web evolution

• Web today• “So, imagine that that

link could have gone to virtually any document you could imagine.”

• Web of documents

• Web tomorrow• “but I want to think

about a world where everybody has put data on the web and so virtually everything you can imagine is on the web. and then calling that linked data.”

• Web of data

how do we get to the next web?

• those things that start with http: --we're using them not just for documents now,we're using them for things that the documents are about.

• Semantic web:• URIs – used to

identify data (resources)

• Web 1.0:• URLs – used to

identify documents

relations

url that identifies a data resource

how do we get to the next web?

• TBL’s rules:– All kinds of conceptual things, they have names

now that start with HTTP.– I get important information back about the data

I’m looking up using a standard format– when I get back that information it's got

relationships

How do we create the semantic web

• write a program to take the data, extract it from Wikipedia, and put it into a blob of linked data on the web, which he called dbpedia.

How do we create the semantic web

• write a program to take the data, extract it from Wikipedia, and put it into a blob of linked data on the web, which he called dbpedia.

• American government data would be available on the Internet in accessible formats (england’s data already is)

How do we create the semantic web

• write a program to take the data, extract it from Wikipedia, and put it into a blob of linked data on the web, which he called dbpedia.

• American government data would be available on the Internet in accessible formats (england’s data already is)

• data is about our lives. You just -- you log on to your social networking site, your favorite one, you say, "This is my friend." Bing! Relationship. Data. You say, "This photograph, it's about -- it depicts this person. "

How do we create the semantic data?

• Extract data from web sites and publish it in semantic formats

• When you develop a web site make sure the data is also available in semantic formats

• Fetch semantic data from social web sites

What is it good for?

• Answer questions based on relations between different data concepts:– What proteins are involved in signal transduction and

also related to pyramidal neurons?– All soccer players, who played as goalkeeper for a club

that has a stadium with more than 40.000 seats and who are born in a country with more than 10 million inhabitants (dbpedia example)

• Query the web like you would query a database!

Web 2.0 + Semantic Web

• => Social Semantic Web• social semantic web is all about everybody

doing their bit and it creates an incredible resource because everybody else does theirs. And that is what linked data is all about. It's about people doing their bit to produce a little bit, and it all connecting.

What I want you to do

• Create linked data and make it available on the web– Choose a domain that you’re interested in– Make an ontology of the domain (linking it to existing

ontologies)– Extract data from the web and create a semantic

repository – Make the data available for search by other

applications– Create a web application that uses the semantic data

that you have

What others want you to do• http://challenge.semanticweb.org• Challenge at the biggest international conference• The requirements represent practically the

guidelines for the development of the Semantic Web

• Minimal requirements – also needed for our project

• Additional Desirable Features – what you will actually need for a commercial product.

Minimal requirements• The application has to be an end-user application • The information sources used

– should be under diverse ownership or control– should be heterogeneous (syntactically, structurally, and semantically)– should contain substantial quantities of real world data

• The meaning of data has to play a central role.• Meaning must be represented using Semantic Web

technologies.• Data must be manipulated/processed in interesting ways to

derive useful information and• this semantic information processing has to play a central role

in achieving things that alternative technologies cannot do as well, or at all;

Additional Desirable Features

• The application provides an attractive and functional Web interface (for human users)

• The application should be scalable (in terms of the amount of data used and in terms of distributed components working together). Ideally, the application should use all data that is currently published on the Semantic Web.

• Rigorous evaluations have taken place that demonstrate the benefits of semantic technologies, or validate the results obtained.

• Novelty, in applying semantic technology to a domain or task that have not been considered before

Italic=interesting from the research point of view

Bold = interesting from the commercial point of view

Additional Desirable Features

• Functionality is different from or goes beyond pure information retrieval

• The application has clear commercial potential and/or large existing user base

• Contextual information is used for ratings or rankings• Multimedia documents are used in some way• There is a use of dynamic data (e.g. workflows), perhaps in

combination with static information• The results should be as accurate as possible (e.g. use a

ranking of results according to context)

Examples: Semantic Web Challenge winners - 2010

• NCBO Resource Index: Ontology-Based Search and Mining of Biomedical Resources – winner 2010

• http://www.cs.vu.nl/~pmika/swc/submissions/swc2010_submission_4.pdf

• Uses ontologies on BioPortal to annotate resources with concepts from the ontologies

• Semantics used in finding synonyms, autocomplete on search, identify hierarchies of concepts

Examples: Semantic Web Challenge winners - 2010

• Linking Open Government Data http://logd.tw.rpi.edu/

• http://www.cs.vu.nl/~pmika/swc/submissions/swc2010_submission_16.pdf

• The TWC LOGD Portal is a semantic web application dedicated to publishing Linked Data versions of OGD and sharing tools, services and expertise supporting an OGD ecosystem. It serves data users ranging from informed citizens, to domain experts, to developers consuming and creating novel applications enriched by government data.

Examples: Semantic Web Challenge winners - 2010

• shortipedia.org • http://www.cs.vu.nl/~pmika/swc/submissions

/swc2010_submission_18.pdf• Aggregating semantic data + curating by

volunteer users (just like wikipedia)

Examples: Semantic Web Challenge winners - 2009

• http://www.cs.vu.nl/~pmika/swc/documents/TrialX-healthx-iswc09-challenge.pdf - matching patients with clinical trials based on patient records

• http://www.cs.vu.nl/~pmika/swc/documents/VisiNav-paper.pdf Exploration of web datasets

• http://www.cs.vu.nl/~pmika/swc/documents/Sig.ma:%20Live%20views%20on%20the%20web%20of%20data-sigma.pdf Visualisation of the web of data

Examples: Semantic Web Challenge winners - 2008

• paggr.com – creates mashups from semantic data

• DBPediaMobile – integrates DBPedia data with Google Maps

• HealthFinland - single national entry-point for health information, health promotion and health-related news

Evolution of the domain

2008 2009 2010

Output data in semantic formats

Aggregate data on a small scale

Visualize dataDevelop tools

Develop tools (visualisation)

Aggregating data on larger scale from a small

number of sources

Aggregate data on a large scale

Complex applications that take advantage of

all the existing data and tools

Evolution from development of tools, small applications, output of semantic data from a single domain to

complex applications aggregating large number of data sources providing complex services

Example• Domain: Romanian Tourism• Ontology concepts: Hotel, Resort, Activity,

City, Camera,…• Data sources: tourism web sites• Semantic interogations

– Hotel at least 2 stars where you can practice archery– Hostel in the Apuseni mountains with a place where the

children can play– Hotel that the girlfriend would like:)

Nume: Rating (nr stele)

Contact: foaf:Person

Facilități

How do you gain points

• 5 points exam • 5 points project – described in the previous

slides

http://www.ted.com/talks/tim_berners_lee_the_year_open_data_went_worldwide.html

References

• http://www.scientificamerican.com/article.cfm?id=the-semantic-web

• http://www.ted.com/talks/tim_berners_lee_on_the_next_web.html