Semantic Web World Wide Web Consortium Keio University/Environmental Information Tatsuya Hagino

Semantic Web by Tatsuya HaginoTatsuya Hagino Table of contents Semantic Web Development of Web Tim Berners-Lee's Goal of Web Semantic Web is not HTML Web What Semantic Web can do - Example - Transation and Interaction Semantic Web is Metadata Web Semantic Web Architecture

Development of Web 1.HTML Separate structure and presentation Accessibility HTML 4.01 is the current and final version of HTML HTML 4.01 has three DTDs Strict Transitonal Frameset 1.XML New Standard for Internet Document Easy to process Mixing documents using namespace Generalize HTML ideas Stylesheet: XSL, XSL-T Hyperlink: XLink, XPointer XML Schema for more powerful constraint XML base Web document XHTML MathML SVG SMIL 1.Semantic Web Next Generation Web Machine can understand Metadata space

Tim Berners-Lee's Goal of Web Human to human communication Information available for anytime, anywhere and anyone. HTML Human to machine communication Machine solves problems Semantic Web

Semantic Web is not HTML Web HTML documents are for human to read and understand. Metadata in Semantic Web is for machine to process and understand. Metadata data for data RDF (Resource Description Framework) is metadata of Web Metadata history PICS (Platform for Internet Content Selection)

What Semantic Web can do - Example - Plan a trip to Boston Current Web 1.Use search engine to list airlines. 2.Check each airline for suitable flights, and decide the airline company. 3.Use search engine to list travel agencies. 4.Check each travel agency for price of the ticket, decide the travel agency, and actually make a reservation. 5.Figure out how to buy the ticket (how to pay). 6.Check Narita express and reserve one. 7.Use search engine to list hotels at Boston. 8.Check each hotel, decide the hotel and make a reservation. 9.Print out the information about flight, Narita express and hotel. Semantic Web 1.Ask to list available flights to Boston for any airline with low price. Pick one and it automatically reserve the flight. 2.It also reserve Narita express automatically. 3.Then, it automatically search hotels at Boston which is convenient for the business. Pick one and it automatically reserve the hotel. 4.All the information is put into your handheld device. 5.It may also put restaurant phone numbers and other useful information into the handheld device.

Transation and Interaction Current Web HTML form CGI HTML result page Query result can only be understandable by human. Semantic Web Metadata query (HTML form may generate it) Metadata result (with HTML for human readability) Machine can understand and further process

Semantic Web is Metadata Web Machine communication each other Apply the design principle of the Web Interoperability Evolution Decentralization Use RDF for metadata Use RDF Schema for basic type definition (class hierarchy) Use Ontology to cope with different vocabulary

Semantic Web Architecture