Semantic Web - Many things to many people

The World Wide Web Consortium

• International consortium directed by Tim Berners-Lee
• Mission: "Lead the Web to its full potential"
• Hosts: MIT, ERCIM, Keio University
• Defines Web standards: HTML, XML, Web Services, Semantic Web
• W3C track record: building infrastructure to address technical and social needs of the Web

Building a Community focused on Developing Web Standards.

23 Activities / 60 Working, Interest and Coordination Groups, supported by the Team

Semantic Web

Data Integration at Web Scale

Enabling a Web of Data

• Framework to facilitate integration
• Capability of connecting data it to its definitions and context
  • E.G. not just "color" but a concept denoted by a Web identifier: <http://pantone.tm.example.com/2002/std6#color>
• Functionality to draw new conclusions

Semantic Web Goal

Enabling more effective collaboration and reuse of data at various scales

• Personal, group, organization, community, web

Reducing the technical and social costs for effective integration of networked data

Moving from a Web of Document to a Web of Data

What is a Web of Data?

Thinking back a bit... circa 1993 FTP, Gopher and Archie: popular for sharing resources on the Internet Stopped at the file level

What is a Web of Data? - Continued

Thinking back a bit... circa 1994 HTML and URIs Markup language and means for connecting resources Below the file level Stopped at the text level

A Web of Data

XML, RDF, OWL and URIs Markup language and means for connecting resources Below the file, text level At the data level

Joining the Web: Data in RDF and OWL ...

...merges just like that.

Enabling technologies

• URI - decentralized identifiers
• XML - common syntax
• RDF - common data model; grounded in the web
• RDFS - primitives for declaring classes, properties; limited logical inference
• OWL - contraints, equivalence, etc.; richer logical inferences

See Also: Ivan Herman's tutorial for details regarding these specifications

Legos as Data Building Blocks ...

... enabling many things

Wrapping, Enhancing the Existing Web

• Web Evolution not Revolution
• Exposing data hiding in documents, servers and databases
• Machine Processible data on the Web

Semantic Web Technologies

• Semantic Web foundation specifications RDF, RDF Schema and OWL are W3C Recommendations as of Feb 2004 (press release and testimonials)
• Standardization work is underway in Query, Best Practices and Rules
• Goal of moving from a Web of Document to a Web of Data

Semantic Web Standards

• Open standards, commercial and open source and tools - technologies for modeling real world things; sharing these models across the Web.
• Focus is on Web Evolution
• Web Evolution causing a quiet data revolution

Changing views in the marketplace

• Things change, plan up front for it
• Desire to free data from the application that created it
• More flexible, customized information services / products
• The value in "as needed" data integration
• Big wins come from many little ones
• The power of links - network effect
• Open-world, open solutions are cost effective
• Importance of "Partial Understanding"

Space and Time connect many things

Demonstration

• Must have books and coffee ...

Problem

Health Services integration problem in Rhode Island:

• Food pantries on one site
• Shelters on another
• Homeless meal sites
• Health Services locations

Solution

Lots of traditional manual work reduced to a short amount of time using Piggy Bank / Semantic Bank.

What makes it possible? Piggy Bank

Personal and collaborative information management Facilitate the management, combination of data and services Solvent: Interactive Tool for helping exract data from particular web site

Vodafone - Live Mobile Portal

Search application (e.g. ringtone, game, picture) using RDF better search : page views per download decreased 50% increased revenue : ringtone up 20% in 2 months Bringing goods closer to customers increased sales RDF was key factor in making this possible

Nokia - Semantic Web enabled forum.nokia.com

Oracle

• Oracle Database 10.2
• Native RDF store
• Converters / loaders for existing RDF data
• RDF Query - An RDF_MATCH function which can be used in SQL to find graph patterns in RDF (similar to SPARQL)
• SeeAlso: Over 100 Partners Thoroughly Test and Support Oracle Database 10g Release 2 and Semantic Technologies Center

FOAF Friend of a Friend

Creating a Web of machine-readable homepages describing people, the links between them and the things they create and do

FOAF Vocabulary Specification

 <foaf:Person rdf:about="http://www.w3.org/People/EM/contact#me">
  <foaf:name>Eric Miller</foaf:name>
  <foaf:mbox rdf:resource="mailto:em@w3.org" />
  <foaf:homepage rdf:resource="http://www.w3.org/People/EM/" />
  <foaf:img rdf:resource="http://www.w3.org/People/EM/s00782" />
  <foaf:knows rdf:resource="http://www.w3.org/People/Berners-Lee/card#i" />
 </foaf:Person>

Navigating : Foafnaut

Distributed RDF/XML records describing people, who they know, projects they work on, etc. Web interface for displaying complex data Benefits of SVG, SMIL, RDF integration Open source collaboration ( credits) Example of RDF network effect combining FOAF and RDF image co-depiction ( demo)

Editing: SWOOP

Hypermedia-based Featherweight OWL Ontology Editor Browser look-feel Inline editing Multiple Ontology Support (Browsing, Mapping, Comparison) impressive debugging capabilities

Finding: GoPubMed

Query is submitted to PubMed and the resulting abstracts are classified using Gene Ontology Example: 'aspirin inhibits'

Lots of tools

For the developer

• RDF frameworks for specific languages: RDFStore (Perl), RAP (PHP), SWI-Prolog (Prolog), Jena (Java), Sesame (Java), Redland: general RDF Framework, with bindings to C, C++, C#, Python, and with SPARQL facilities (Rasqal)
• RDF storage systems: (Sesame, Kowari, Tucana, Gateway, @Semantics RDFStore, 3Store, Jena's Joseki, Intellidimension's InferEd, Oracle Database 10g)
• Editors: Protege, SWOOP, Semantic Works, etc.
• Browsers: Haystack, mspace, Piggy Bank, etc.
• Directories: Swoogle, SchemaWeb, etc.

See the tool list at W3C for more developer tools

Lots of commercial products

For the business analyst

• Adobe's XMP, Altova's SemanticWorks, Oracle's 10.2, Cerbra Server, RDF Gateway and InferEd, Aduna's Metadata Server, Northrop Grumman's Tucana Suite, Siderean's Seamark Navigator, Profium's Semantic Information Router (SIR), Teranode's XDA, Language and Computing's LinKFactory, etc.

See the Semantic Web list of Commercial applications for more

Lots of demos and applications

For those interested in learning more

• Partners Healthcare Systems on 'Clinical Knowledge Management' - Tonya, Vipul
• Agfa on 'Connected Knowledge' - Helen, Jos
• Active Semantic Electronic Medical Record, an application of Active Semantic Documents in health care - Amit
• BioDash using Haystack - Dennis, Eric
• Language & Computing's Knowledge Discovery Platform accelerates drug development through knowledge extraction and semantic integration - Davide

Also, The Semantic Web Best Practice and Deployment working group maintains a list of additional Semantic Web applications and demos.

HCLS

• Share use cases, applications, demonstrations, experiences
• Exposing collections
• Developing vocabularies
• Building / extending (where appropriate) core vocabularies for data integration

GRDDL

Gleaning Resource Descriptions from Dialects of Languages

A mechanism for connecting XHTML (e.g. microformats) and XML dialects with the Semantic Web.

1. Pick a way of expressing data in XHTML, and get an XSLT transformation to RDF; for example:

• Encoding Dublin Core Metadata in HTML and dc-extract.xsl
• GeoURL markup and grokGeoURL.xsl
• RDF Site Summaries in XHTML, using home2rss.xsl

GRDDL 2

2. Make links from your XHTML data to the transformation, using the transformation link type:

<html xmlns="http://www.w3.org/1999/xhtml">
  <head profile="http://www.w3.org/2003/g/data-view">
    <title>Some Document</title>
    <link rel="transformation"
       href="http://www.w3.org/2000/06/dc-extract/dc-extract.xsl" />
    <meta name="DC.Subject"
       content="ADAM; Simple Search; Index+; prototype" />
    ...
  </head>
  ...
</html>

GRDDL 3

3. Reference the GRDDL profile to make it clear what that transformation link type means:

<html xmlns="http://www.w3.org/1999/xhtml">
  <head profile="http://www.w3.org/2003/g/data-view">
    <title>Some Document</title>
    ...

GRDDL XSLT service demo, example

• online GRDDL demo service by Dom, Nov 2003.
  • check its output with the W3C RDF Validation service
• An example home page for Joe Lambda shows DC, GeoURL, RSS, FOAF, and Creative Commons Licenses.

SPARQL

• Query language for RDF
• Common protocol and interface to expose databases / application data as RDF
• "Join the Web"
• More information: Data Access working group

SKOS

• Simple Knowledge Organization System (SKOS)
• RDF vocabulary to support the declaration / reuse of knowledge organization systems (KOS)
• Core
  • model for expressing the basic structure and content of concept schemes (thesauri, classification schemes, subject heading lists, taxonomies, etc.)
• Work on Mapping and Extensions

Conclusions

• Semantic Web is here
• More work is needed
• You can help!

More Information

• Slides are available at http://www.w3.org/2006/Talks/1125-hclsig-em/
• W3C - http://www.w3.org/
• Semantic Web Home Page - http://www.w3.org/2001/sw/
• Me - Eric Miller, em@w3.org