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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
…
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.
