Semantic Web Overview of Concepts and Issues Greg
Semantic Web Overview of Concepts and Issues Greg Wheeler Union College Computer Management System
Potential Scenario
Potential Scenario
Potential Scenario
Potential Scenario
Potential Scenario
Potential Scenario
Potential Scenario
Potential Scenario
Potential Scenario
Potential Scenario
Potential Scenario
Potential Scenario
Terms from Scenario n n n Agent, Semantic Web Agent, Doctor’s Agent Local Devices Volume Control Prescribed Treatment In-Plan Excellent or Very Good n n n Acceptable Radius Stricter Preferences Access Certificates Less Important Complete Trust Details
Presentation Agenda n n Background Key Organizations Current Web Semantic Web
Background: Internet Revolution n Broadcasting Medium Information Dissemination Medium for Collaboration and Interaction Regardless of Geographic Location
Background: WWW n n Integrated Disparate Information Systems Information Sharing Communication Commerce
Web Evolution Cycle Human Communication Machine Communication
Key Organizations n n World Wide Web Consortium (W 3 C) Semantic. Web. org
Key Organizations: W 3 C n n Created 1994 Lead WWW to Full Potential Promote its Evolution Ensure Interoperability
Key Organizations: W 3 C n n n n Universal Accessibility Semantic Web Trust Interoperability Evolvability Decentralization Cooler Media
Key Organizations: n n Explicit facility to demonstrate Ideas and Concepts Automated Community Portal Semantic. Web. org
Current Web n n n Underpinnings of Semantic Web Somewhat Parallel Development Important Concepts and Approaches
History of the Internet
History of the Internet n n Technological Evolution Operations and Management Social Considerations Commercialization
Internet Technical Concepts n n Open Architecture Networking Distinct Independent Networks Communications on a Best Effort basis Simple Gateways and Routers
Internet Social Concepts n n n No Global Control at the Operations Level Open Source Collaboration
Future of Internet If the Internet stumbles, it will not be because we lack for technology, vision, or motivation. It will be because we cannot set a direction and march collectively into the future. [1] ISOC: All About the Internet: History of the Internet [http: // www. isoc. org/internet/history/brief. shtml]
History of the WWW n n n Invented in 1990 Invented by Tim Berners -Lee Wrote: n n First WWW Client and Server HTTP HTML Single Requirement: URI
History of the WWW: Rules n n n Device Independence Software Independence of Scale Internationalization Accessibility Quality Independence
Issues with Current Web n n n No Machine to Machine Communication Missing Information about Information Quality Independence
Semantic Web: Definitions
Semantic Web: Definitions
Semantic Web: Definitions The Semantic Web is the abstract representation of Data on the World Wide Web, based on the RDF standards and other standards to be defined. It is being developed by the W 3 C, in collaboration with a large number of researchers and industrial partners. It is based on the Resource Description Framework (RDF), which integrates a variety of applications using XML for syntax and URIs for naming.
Semantic Web: Definitions The Semantic Web is an extension of the current web in which information is given well-defined meaning, better enabling computers and people to work in cooperation.
Semantic Web: Definitions The Semantic Web is a vision: the idea of having data on the web defined and linked in a way, that it can be used by machines – not just for display purposes, but for using it in various applications.
Semantic Web
Uniform Resource Identifiers (URI) n n All things on the Web require a URI Most known URI – URL Administration of URIs is Decentralized Anyone can create a URI
Semantic Web
e. Xtensible Markup Language (XML) n n n n Media Independent Electronic Publishing Inexpensive off-the-shelf tools Saves training and development costs Increases Reliability Provides Underpinnings for Semantic Web Encourages Platform Independent Protocols for Data Exchange Works with Style Sheets
e. Xtensible Markup Language (XML) <sentence> <person href=http: //www. wheelerclan. us/>I</person> am attending <institution type=“university” href= “http: //www. wheelerclan. us/my. University”>Union College</institution>. </sentence>
e. Xtensible Markup Language (XML) <sentence xmlns=“http: //example. org/xml/documents/” xmlns: c=http: //institutions. example. net/xmlns/> <c: person c: href=http: //www. wheelerclan. us/>I</c: person> am attending <c: institution type=“university” c: href= “http: //www. wheelerclan. us/my. University”>Union College</c: institution>. </sentence>
Semantic Web
Resource Description Framework (RDF) n n Declarative language that provides a standard way for XML to represent metadata. Integrates applications and agents. Framework to Develop Vocabularies Enables sharing of the Vocabularies
Resource Description Framework (RDF) <RDF xmlns="http: //www. w 3. org/1999/02/22 -rdf-syntax-ns#" xmlns: dc="http: //purl. org/dc/elements/1. 1/"> <Description about="http: //www. w 3. org/Press/99 Folio. pdf"> <dc: title>The W 3 C Folio 1999</dc: title> <dc: creator>W 3 C Communications Team</dc: creator> <dc: date>1999 -03 -10</dc: date> <dc: subject>Web development, World Wide Web Consortium, Interoperability of the Web</dc: subject> </Description> </RDF>
RDF Schemas n Defines n n n n Meaning Characteristics Relationships Constraints on Potential Values Inheritance of Properties Identifies which Vocabulary is used through URI to RDF Uses XML Namespaces
RDF Conversions
Semantic Web
Ontology n n Formally defines a common set of terms used to describe and represent a domain. Include computer usable definitions of basic concepts and relationships among them.
Ontology n n Need to have a significant degree of structure Must describe n n Classes in the many domains of interest Properties (attributes) those things have Usually expressed in logic-based language Enable detailed, accurate, consistent, sound and meaningful distinctions among classes, properties and relations.
Semantic Web
Logic/Proofs n n n State logic principle Permit Computer to reason using Principle Combine with other logic through Semantic Links
Semantic Web
Web of Trust n n Digital Signatures Trust Relationships n n You trust people They trust people Those people trust people Etc.
Agents n n Software programs Collect Web Content from Diverse Sources Process the data Exchange results with other programs
Agents: Example n n Find the Ms. Cook you met at a trade conference last year You don't remember her first name You do remember that she worked for one of your clients Her son was a student at your alma mater.
Agents: Example n Searches for people named “Cook” n n Not that are cooks Not the Cook Islands, etc. Matches employment to your client list Follows links to their children’s pages for match to alma mater
Agents: Example n Allows you to review the proof
Terms from Scenario n n n Agent, Semantic Web Agent, Doctor’s Agent Local Devices Volume Control Prescribed Treatment In-Plan Excellent or Very Good n n n Acceptable Radius Stricter Preferences Access Certificates Less Important Complete Trust Details
Terms from Scenario n n n Agent, Semantic Web Agent, Doctor’s Agent Local Devices Volume Control Prescribed Treatment In-Plan Excellent or Very Good n n n Acceptable Radius Stricter Preferences Access Certificates Less Important Complete Trust Details
Terms from Scenario n n n Agent, Semantic Web Agent, Doctor’s Agent Local Devices Volume Control Prescribed Treatment In-Plan Excellent or Very Good n n n Acceptable Radius Stricter Preferences Access Certificates Less Important Complete Trust Details
Conclusion
Discussion/Questions
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