2. The current Web represents information using
-natural language (English,Hungarian,Chinese).
-graphics,multimedia, page layout.
Humans can process this easily
- can deduce facts from partial information.
- can create mental association.
- are used to various sensory information.
3. Tasks often require to combine data on the Web.
- Hotel and Travel information may come from different
websites.
- searches in different digital libraries.
Humans can combine these information easily.
- even if different terminologies are used.
However , machines are ignorant.
- partial information is unusable.
- difficult to make sense from, e.g ,an image.
- difficult to combine information automatically.
4. Semantic Web - coined by Tim
Berners-Lee
inventor of WWW, URI, HTTP, HTML and Semantic
Web.
“ a web of data that can be processed directly and
indirectly by machines . “
to access the Web more intelligently and perform
tasks on behalf of users .
evolution of the current Web by enabling users to
find, share, and combine information more easily .
5. Why not just google ?
Currently, users search for data on the Web by asking
questions that are of the form : “which documents
contain these words and phrases ”
The Semantic Web will involve more related questions ,
relationships, and trust .
Instead of word matching the web will be able to show
related items showing new relationships.
9. RDF (Resource Desciption
Framework)
RDF is the foundation of the semantic web .
RDF = a simple conceptual data model (GRAPH).
RDF model = set of RDF triples .
(subject, verb, object).
A Sentence
Jane sells books.
subject
predicate
object
10. RDF - Resource
Resource is anything that has identity (URI).
-Jane, Book.
(a govt agency, a human , an abstract concept)
RDF – Description
several statements describing the resource.
RDF – Framework
It is needed to enable humans and machines to make
and understand statements .
- Natural languages like English.
11. Human brain uses logic
Mary is a mother.
A mother is a parent.
Therefore, Mary must be a parent.
ONTOLOGY
Precise explanation of terms and reasoning in a subject
area.
- Computers can act as if they understand the
information they are handling.
The facts stored in the semantic web will change over
time as the true state of world changes.