1. Knowledge Representation (Part I)
Jan Pettersen Nytun
Knowledge Representation Part I, JPN, UiA

2. Facts/understanding about a particular subject
a symbol or thing which represents something else (refers to, stands for) is is
Knowledge
Representation
AI requirement
when to use
computer-understandable form
when we can not use the “original”, like things in the natural world or concepts
Knowledge Representation Part I, JPN, UiA

3. Knowledge Representation Part I, JPN, UiA
From Wikipedia, the free encyclopedia (Knowledge representation and reasoning)
Knowledge Representation (KR) is an area of artificial intelligence research aimed at representing knowledge in symbols to facilitate inferencing from those knowledge elements, creating new elements of knowledge.
Knowledge Representation Part I, JPN, UiA

4. Knowledge Engineering
Get knowledge about some subject and represent it in a computable form for some purpose.
The knowledge engineer tells the system what is true.
The system knows how to infer new facts and solutions – the user may form questions and then the system gives answers.
Knowledge Representation Part I, JPN, UiA

5. Knowledge Representation Part I, JPN, UiA
Knowledge Base
A database for knowledge management
It provides means for information to be:
Collected
Organized
Shared, searched and utilized (new information may be inferred)
Knowledge Representation Part I, JPN, UiA

6. What is an Ontology (in Philosophy)
Ontology studies the nature of being and existence.
Smith [1] the essence of ontology: “provide a definitive and exhaustive classification of entities in all spheres of being.”

7. What is an Ontology in Computer Science
Knowledge represented in a formal way:
- a hierarchy of concepts within a domain,
- a shared vocabulary to denote the types,
- properties and interrelationships of those concepts.

8. What is an Ontology (in Computer Science)
An ontology is a specification of a conceptualization that is designed for reuse across multiple applications and implementations. …a specification of a conceptualization is a written, formal description of a set of concepts and relationships in a domain of interest.
Peter Karp (2000) Bioinformatics 16:269

9. References
[1] Book: David Poole and Alan Mackworth, Artificial Intelligence: Foundations of Computational Agents, Cambridge University Press, 2010,
Sowa, John F. (2000) Knowledge Representation: Logical, Philosophical, and Computational Foundations, Brooks/Cole Publishing Co., Pacific Grove, CA.
Artificial Intelligence: Structures and Strategies for Complex Problem Solving (Addison-Wesley), George F. Luger
Smith Barry. Accessed 24th of March, 2013, Ontology: Philosophical and Computational. http: //ontology.buffalo.edu/smith/articles/ontologies.htm
Quine WVO. On What There Is. Review of Metaphysics 1948;p. 21–38.