Semantic Navigator: Use of Semantic Data in Web Navigation Jan - - PowerPoint PPT Presentation

Semantic Navigator: Use of Semantic Data in Web Navigation

Jan Michelfeit, Tomáš Knap

michelfeit.jan@gmail.com Faculty of Mathematics and Physics Charles University, Prague Czech Republic

emantic Navigator

 Tool for navigation on the web of documents  Mozilla Firefox extension  Supports a familiar paradigm

• f searching for information

in web documents

 Solves some of the issues with traditional web

search using a Semantic Web search engine

2 Charles University in Prague

Problems with traditional web search

 Search term ambiguity

The film "Casino"? A Las Vegas Casino? Online Casino?

 No support for search of property values

Search for "Casino release year"? "Casino produced"? " Casino released "? "Casino opening weekend"?

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Problems with browsing LD

 Ordinary users are not used to it  Extra effort to validate provenance  Estabilishing trust to the data source

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http://www.w3.org/TR/rdf-primer/

We‘ve got a solution

 Use semantic data for web search  Suggest properties from ontologies  Provide quick access the search without

leaving your browser

 Adhere to the traditional paradigm

locate documents – find information manually

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Goals of Semantic Navigator

 Make web navigation easier in discovering

• more information about a selected entity
• more information about its properties

 Take advantage of technologies such as RDF(a),

microformats or ontologies

 Bring advantages of the Semantic Web search

to ordinary users

 Be versatile, not domain specific

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How to use it

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Highlight resources What you search for Search results

Charles University in Prague

An Example

 Navigate to www.wikier.org1  Presence of RDFa is detected

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1Homepage of Sergio Fernández, used with his kind permission

An Example

 Highlight semantic data with Semantic

Navigator

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An Example

 We want to know more about people that

Sergio knows

→ Click on the resource and select foaf:knows in the menu

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An Example

 We want to know more about people that

Sergio knows

→ Click on the resource and select foaf:knows in the menu

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An Example

 Get suggested people, search for more

documents about them

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More examples

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 semantic-navigator-screencast.avi

Internals

 Mozilla Firefox extension  Uses a Java component (Any23, Jena libraries)  Gets search results from Sindice  Provides suggestions for triple subjects/objects

retrieved from Sindice SPARQL endpoint

 Provides direct access to summaries on Sig.ma

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Internals

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architecture outline

Internals

1) Detect semantic data

• RDFa, microformats, RDF documents linked by a <link> element

2) Extract data and create an RDF graph 3) Optionally import used ontologies (cached) 4) Optionally highlight data in the web page

• includes detection of literal occurences in non-annotated text

5) The users selects what she is interested in 6) Display search results retrieved from Sindice

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step by step

Future work

 Usability for non-technical users  Drop dependency on Java  Deal with insufficient identifier sharing

 Filter by xml:lang for literals  More sophisticated search - use IFPs, owl:sameAs links,

search by blank nodes

 Filtering and suggestions of properties while typing  Searching for a manually entered keyword 17

what we can improve

Future work

 Publish data in RDFa, microformats etc.  or link to an RDF alternative from HTML  Share identifiers, use owl:sameAs links  Continue the great work on Semantic Web

search engines

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What the world can do for us

Possible future applications

 More general alternative to domain-specific

solutions

 Effortless Wikipedia-like Navigation

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Thank you for your attention

Jan Michelfeit, Tomáš Knap

michelfeit.jan@gmail.com Faculty of Mathematics and Physics Charles University, Prague Czech Republic