Web rules

Technical:

Use URIs for documents and anchors
Ladder of authority to interpret
Use standards (HTTP. xHTML, SVG, CSS, DOM, XSLT, ...)

Social:

Serve useful stuff
Make useful links
Intellectual property, libel & fraud laws

Semantic Web

Technical:

Use URIs for documents and concepts
Same ladder of authority
Standards: (RDF, OWL, SPARQL*, RIF**)

Social:

Serve useful stuff
Make useful links
Share ontologies
Agree on ontologies

SW: Everything has a URI

Don't say "colour" say <http://example.com/2002/std6#col>

The relational database

A database's row, column and cell are subject, property and value.

The element of the Semantic Web

Can be encoded in XML
Simplicity and mathematical consistency
This is called Resource Description Framework (RDF)

Semantic web includes tables,...

...merges just like that.

more circles and arrows superim

Subject and object node using same URIs

RDF: Semantic links - "Joining the Web"

Links between column headings

Verb/predicate/Property using same URIs

Communities and Vocabularies

Universal WWW must include communities on many scales

Applications connected by concepts

Its like a metro, the way the lines of common concepts connect the stations of different applications

For example in biopax

Venn diagram showing ontologies overlapping by certain common terms

[Diagram: Joanne Luciano, Predictive Medicine; Drug discovery demo using RDF, Sideran Seamark and Oracle 10g]

Fractal Web of concepts

Across boundaries of scale -- personal, group, global
Varying access levels
Tension between local and global standards
Society is a fractal tangle, so must SW be.
Personal interactions on multiple scales

The semantic web is about allowing data systems to change by evolution not revolution

Total Cost of Ontologies (TCO)

Assume :-) ontologies evenly spread across orders of magnitude; committe size as log(community), time as comitee^2, cost shared across community.

Scale	Eg	Committe size	Cost per ontology (weeks)	My share of cost
0	Me	1	1	1
10	My team	4	16	1.6
100	Group	7	49	0.49
1000		10	100	0.10
10k	Enterprise	13	169	0.017
100k	Business area	16	256	0.0026
1M		19	361	0.00036
10M		22	484	0.000048
100M	National, State	25	625	0.000006
1G	EU, US	28	784	0.000001
10G	Planet	31	961	0.000000

Total cost of 10 ontologies: 3.2 weeks. Serious project: 30 ontologies, TCO = 10 weeks.
Lesson: Do your bit. Others will do theirs.
Thank those who do working groups!

Clients of the RDF bus

New data applications can be built on top of RDF bus, for example:

db to sw

Future: Stack of expressive power

architectural layers

The Semantic Web Wave

The wave is coming...get out your surfboard

Current Semantic Web work at W3C

(*New!)

Adoption challenges

Paradigm shift all over again
Data is trickier, esp. to design logic languages
Need for smaller incubator like HEP
Data is less exciting with no browser
Fear of having to make ontologies

Good news

Logic discussions are getting done (OW, SPARQL, RIF,...)
Life sciences is an incubator community, also Geo, FOAF,...
TCO is finite
Startups
Major vendors are moving it into products
We have some ideas about actually making a user interface!

Introduction to the Semantic Web

Overview