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Semantic Web 2.0

Dr. Harry ChenCMSC 491S/691S

April 21, 2008

Agenda

Revisit the Semantic Web (SW)Think about SW in the context of …

Web 2.0 Social Web

Speculate on the future Web

The Semantic Web

It’s a vision about the Web Allows data to be shared and reused across

application, enterprise and community boundaries

Nothing new here! It was part of the goal in creating Web 1.0 Why should we use the Web if we can’t share

and reuse information?

Semantic Web Research

W3C Semantic Web ActivityRooted in AI Knowledge Representation

Some said too much KR hindered the development of the Semantic Web

Personally, I think that’s debatable Since 2000, many tools and standards

have been developed under the SW flag.

Most Important SW Components

Ontology RDF

URI

SemanticWeb

URI

Uniform Resource Identifier http://foo.com/bar/mumble.html#pitch

Unambiguous Unlike natural lang.: “G. Bush” and “G. Bush”

Can be used in logical inference If we found two resources having the same

URI, we can assume they are describing the same thing.

RDF

An unordered collection of statements that describe Web Resources People, Place and Things Relationships

RDF Statement TripleTripe (subject, predicate, object)Resources are identified by URI

View RDF as a Graph

Source: http://www.w3.org/TR/2003/PR-rdf-primer-20031215/fig1dec16.png

Publish RDF on the Web

How do you publish RDF statements?Issues to consider

Publish for what purpose? Who will consume those stmts? And, how? How to compose and edit those stmts? Who publishes those stmts – human or

machine?

RDF Representations

<rdf:RDF ……..> <….> <….></rdf:RDF>

XML EncodingGraph

stmt(docInst, rdf_type, Document)stmt(personInst, rdf_type, Person)stmt(inroomInst, rdf_type, InRoom)stmt(personInst, holding, docInst)stmt(inroomInst, person, personInst)

Triples

RDFData Model

Good for Machine

Processing

Good For HumanViewing

Good For Reasoning

RDF is a simple language for building graph based representations

RDF Demo

http://www.w3.org/RDF/Validator/

Ontology (in information systems)

A dictionary of some sort.An explicit representation of how to

represent the object, concepts and other domain entities and relationships among them. e.g., database schemas and UML diagrams

Ontology (in the Semantic Web)

Use RDF to create a new language for describing Web Resources and the relationships among them. RDF-S OWL

OWL

Ontology Demo

Wine Ontology in SWOOP

Wine Agent

Got Semantic Web?

Ontology RDF

URI

SemanticWeb

Why the Semantic Web remains to be a “research-ish” thing?

Missing a Bridge

The Web as we know it The Web that we hope to createGoogle

AmazonYouTube

HTML…

Knowledge sharingInformation reuse

Machine-readable WebOntology

…

The “Missing Bridge” Problem

Two causes: We don’t know what kind of bridges to build. We had the wrong design. (bridge or tunnel?)

Semantic Web’s Missing Bridge

“Don’t know what bridge to build” Many people misunderstood SW Many people have misconceptions about SW

“We had the wrong design” Semantic Web == “Artificial Intelligence” Web Logical inference must underpin every SW app Large ontology is required for building SW app Maybe we need something different from OWL,

RDFS and RDF.

Misconception #1

The Semantic Web will bring about a “killer” application!

SW is not Web 2.0

Web 2.0 is about building a new kind of highly interactive and dynamic Web applications

Semantic Web is about data – how to share it, reuse it and integrate it.

Misconception #2

Web 2.0, JSON, Ajax will “kill” the Semantic Web

SW is not Web 2.0

JSON and Ajax enable sites to publish data for building mashup.

But, they are not suitable for serious data integration and knowledge sharing tasks. Remember the “Mash Maker” demo that Wes

has shown us?

Misconception #3

The Semantic Web is all about building an AI Web

Semantic Web is not AI Web

The Web is for people, not for machines.When building Web applications, anything

you develop, whether it’s an AI program or non-AI program, they should serve people.

Misconception #4

Large ontologies are required for building successful Semantic Web applications

Bigger is not always better!

The use of ontology in information systems is a technique to solve a certain kind of problem.

By itself, ontology can’t create any useful Web application.

You are permitted to create SW application using a small or large ontology.

Misconception #5

The Semantic Web is a different Web

We only have one Web

Web 1.0, Web 2.0, Web 3.0 … Web 20.0 will always be the same Web. Unless, we have a completely different Internet

Ideas and research results of the Semantic Web will be seamlessly integrated into, not replacing, the Web

We still haven’t solve the problem

The Web as we know it The Web that we hope to createGoogle

AmazonYouTube

HTML…

Knowledge sharingInformation reuse

Machine-readable WebOntology

…

Let’s do some speculation…

Acting as a futurist…

How will Semantic Web technologies turn out in the future Web?

What technologies and computing trends are likely to stay in the future Web?

How will a social Web influence the adoption of Semantic Web technologies?

What’re the tools essential to the growth of the Semantic Web?

What can you conclude from this video?

http://www.youtube.com/watch?v=JVZ6E9EnJ3I

The Web is here to stay

We live,We work,We socialOn the Web.

HTML is here to stay

We will continue to use HTML to create Web information.

Most people will be editing the Web through HTML or applications that manipulate HTML.

Open Question.

If RDF is the language for describing semantic information on the Web, who is going to create RDF? You, me Robots X?

Social Web and SW

Social Web is about user-created content. YouTube, Facebook, Flickr

The more information they create, the more information needs to be integrated. Mash Maker ManyEyes, Sentiment Analysis, Wiki

Open Question

If the future is about mashup, knowledge sharing and data reuse, how can we “free” data from web sites? Consuming flickr, del.icio.us, youtube data

requires special protocols and data formats Consuming RSS (from CNN, Reuters, my

blogs) requires no understanding of special protocols.

Concluding Remarks

The Semantic Web is vision, not an application technology.

SW is about data – being shared, integrated and reused.

If we resolve our misconceptions about the Semantic Web, we see a bright future for its technologies in Web 2.0 and the Social Web.