Toward The Semantic Deep Web

What The Problem?

Consider a typical web page

Mark-up consists of: rendering information

Semantic content is accessible to humans but not (easily) to computers …

Machine requires Natural Language understanding

Our Goal

Accessing the deep web by various web technologies

e.g. XML Schema, RDF, OWL

Represent the data in a machine accessible way

Enriching ontologies using this data

The Semantic Web 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 co-operation . [Tim Berners-Lee , 2001]

Accessing semantic deep web

Two main approaches-

Ontology plug-in search

Deep web service annotation

Both approaches require a semantic deep web crawler or bot.

Ontology plug-in search Referent Form Search engine replies refers to evokes Concept “ Jaguar“

Ontology plug-in search

Two processes-

Harvesting concepts or deep web form attribute.

Iteratively link this concepts to build enriched ontology.

This ontology provides- - domain specific terms. - useful relationship and further related information.

Deep web service annotation How to represent data in a machine accessible way?

Semantic data signature represented in computational graph

-XML

-RDF

-RDF Schema

-OWL (Web ontology language)

The Semantic Web Layers Standard Standard Standard

XML

User definable and domain specific markup

<course date= “...” > <title> ... </title> <teacher> ... </teacher> <name>...</name> <http>...</http> <students> ... </students> </course> File Format Tree Structure

Why not use XML to represent ontologies?

XML makes no commitment on:

Domain specific ontological vocabulary

Conceptual meaning

course teacher title students name http =

RDF(Resource Description Framework)

A mechanism for annotating data and resources

RDF is a graphical formalism

-for representing metadata about Web resource

-for describing the semantics of information in a machine- accessible way

RDF(S): RDF Schema

Defines vocabulary for RDF

Organizes this basic vocabulary terms and the relations between those terms

-Class, subClassOf, type

-Property, subPropertyOf

-domain, range

Has Supervisor Person subClassOf subClassOf type domain range type

OWL :Web Ontology Language

Ontologies standardize and formalize the meaning of words through concepts

It helps softbots by serving knowledge about synonyms, antonyms, semantic relationship between concept.

Conclusion Ontology helps to find the concepts. Semi-automatic ontology generation from the deep web, quality of ontology measurement(reliability) is challenging. It requires natural language processing.

Reference

Y. Sure and R. Studer. Vision for Semantically-Enabled Knowledge Technologies. Online at: KTweb -- Connecting Knowledge Technologies Communities, 2003.