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

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

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

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

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

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.”

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.

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

References [1] Book: David Poole and Alan Mackworth, Artificial Intelligence: Foundations of Computational Agents, Cambridge University Press, 2010, http://artint.info/ 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.