SENG691I - Knowledge Representation and The Semantic Web

Slideshow Transcript

1. Slide 1: Knowledge Representation and the Semantic Web by Daniel D. Shaw
2. Slide 2: Knowledge Defined i. Expertise and skills acquired through experience or education; the theoretical or practical understanding of a subject. iii. What is known in a particular field or in total; facts and information. v. Awareness or familiarity gained by experience of a fact or situation. Source: Oxford English Dictionary (by way of Wikipedia)
3. Slide 3: Knowledge Representation 5 Roles of Knowledge Representation  A surrogate, a substitute for the knowledge itself, used to determine consequences.  A set of ontological commitments. The definition of the domain a thing is associated with.  One of the aspects of the theory of intelligent reasoning. (Concepts very relevant to AI, but less relevant to what we’re looking at). Source: Davis, Shrobe and Szolovits, 1993
4. Slide 4: Knowledge Representation 5 Roles of Knowledge Representation  A medium for pragmatically efficient computation. Knowledge management facilitators or expert systems rule.  A medium of human expression, such as language. Source: Davis, Shrobe and Szolovits, 1993
5. Slide 5: How do we represent knowledge? <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#“ xmlns:foaf=\"http://xmlns.com/foaf/0.1/\" xmlns:rdfs=\"http://www.w3.org/2000/01/rdf-schema#\"> <foaf:Person rdf:about=\"#JW\"> <foaf:name>Jimmy Wales</foaf:name> <foaf:mbox rdf:resource=\"mailto:jwales@bomis.com\" /> <foaf:homepage rdf:resource=\"http://www.jimmywales.com/\" /> <foaf:nick>Jimbo</foaf:nick> <foaf:depiction rdf:resource=\"http://www.jimmywales.com/ausimgsmall.jpg\"/> <foaf:interest> <rdf:Description rdf:about=\"http://www.wikimedia.org“ rdfs:label=\"Wikipedia\" /> </foaf:interest> <foaf:knows> <foaf:Person> <foaf:name>Angela Beesley</foaf:name> </foaf:Person> </foaf:knows> </foaf:Person> </rdf:RDF> Image Source: http://en.wikipedia.org/wiki/FOAF_(software)
6. Slide 6: Father of the [Semantic] Web Tim Berners-Lee  Actually it’s… Sir Timothy Berners-Lee OM, KBE, FRS, FREng, FRSA  Invented the World Wide Web in 1989.  Director of the W3C.  Early documents in 1998. Published “The Semantic Web” in Scientific American in 2001.  Started formally working on the Semantic Web project at the end of 2004. Image Source: W3C Semantic Web Activity
7. Slide 7: Semantic Web Remember: Semantic = “meaning”
8. Slide 8: Semantic Web “The Semantic Web is a web of data. There is lots of data we all use every day, and its not part of the web. I can see my bank statements on the web, and my photographs, and I can see my appointments in a calendar. But can I see my photos in a calendar to see what I was doing when I took them? Can I see bank statement lines in a calendar?” - W3C Semantic Web Activity
9. Slide 9: Semantic Web “LayerCake” Image Source: W3C Semantic Web Activity
10. Slide 10: Semantic Web “LayerCake”  URI/IRI – links.  XML – interchangeable, structured data.  Resource Description Framework (RDF)  RDF Schema (RDFS)  Rule Interchange Format (RIF) Image Source: W3C Semantic Web Activity
11. Slide 11: Semantic Web “LayerCake”  SPARQL  Web Ontology Language (OWL)  “Trust” – the top layer and the key to realizing the full potential of the Semantic Web. Image Source: W3C Semantic Web Activity
12. Slide 12: Semantic Web in Practice Network aware devices  Interact with other locally aware devices.  Example: Phone that notifies local devices with a volume control that there is an incoming call.
13. Slide 13: Semantic Web in Practice Intelligent Agents  Conduct trusted actions on behalf of the owner with trusted resources.  Example: Intelligent agent book trip for WWW2008.
14. Slide 14: Take-aways for Software Engineers Knowledge Representation  Knowledge and the representation of knowledge is multi-faceted and does not necessarily need to be dealt with as a whole.  Ontologies are important, but imperfect.  Which is more important for you: meaning for computers or meaning for humans?
15. Slide 15: Take-aways for Software Engineers The Semantic Web  After 7+ years, it’s still “emerging”.  In its purest sense, it may never become a reality.  Trust of computer systems, especially the one’s we didn’t create could be a major hurdle.
16. Slide 16: Take-aways for Software Engineers The Semantic Web  The core concepts of The Semantic Web can be applied creatively.  We can sample and mash-up these concepts.  Web 2.0 business have created business value by applying these concepts in simple ways.
17. Slide 17: Knowledge Representation and the Semantic Web by Daniel D. Shaw Thank you!