KM and Semantic Web

Anuj Nanavati

Objective

• Introduction

• Semantic Web components

• Framework for KM on semantic Web

• Impacts of semantic Web on KM

• Technologies– RDF

• Discussion

Semantic Web

• “The Semantic Web is a project that intends to create a universal medium for information exchange by giving meaning (semantics), in a manner understandable by machines, to the content of documents on the Web. It extends the ability of the Web through the use of standards, markup languages and related processing tools”. – wikipedia

• Thought up by Tim Berners-Lee, inventor of the WWW, URIs, HTTP, and HTML

• An extension to the current Web• Currently under control of w3c

Semantic Web Components

• Expressing meaning

• Knowledge representation

• Ontologies

• Agents

Expressing Meaning

• Today's Web is for people not for computers• Document for people and information for agents• In semantic Web Information is given well-

defined meaning, better enabling computers and people to work in cooperation

• Anything can link to anything, no limitations on content and information

• Decentralized ???

Knowledge Representation

• Access to – Structured collection of information – Sets of inference rules

• Automated reasoning• Semantic Web to provide a language for

expressing data and rules for reasoning about the data

• Describing complex Web objects without tricking agents

Ontologies

• Document that defines relation among terms• Taxonomy

– Classes and subclasses of objects– Relation among them

• Inference rules to express relation• Meaning of terms on a Web page can be defined

by pointers from the page to an ontology• Answer indirect complicated questions

Agents

• Software programs• Transfer semantic data among themselves• Service discovery through common

unifying language– Exchanging ontologies– Bootstraping by discovering new ontologies

• Services – Trusted: proofs, digital signatures– searching

Framework for KM on the Semantic Web

Impact of Semantic Web on KM

• Coordination between knowledge and workings of humans with software agents

• Precision in searching for knowledge– Indexing using ontology-based statements

• Problem relevant knowledge retrieval

• Joining various subcultures ???

How?

• XML: Extensible markup language– Basic doc structure with no semantic– Structure to the data

• RDF: Resource description framework

• RSS: Really simple syndication

• URI: Uniform resource identifier

• DAML: DARPA agent markup language

• vCal and vCard

Resource Description Framework - RDF

• Representing information about resources • Language for ontologies• Any resource – not only content• Resources represented by URIs• 3 structural part of a RDF statement

– Subject– Object– Predicate: relation

• “The article is authored by the author”

Article URL Authorauthored-by

Discussion Questions

• Role of AI in semantic Web

• Issues – Security– Privacy– Intellectual property

• Need for humans?