269 SEMANTIC WEB TECHNOLOGIES IN KNOWLEDGE MANAGEMENT ASTA BÄCK, SARI VAINIKAINEN, CAJ SÖDERGÅRD AND HELENE JUHOLA VTT Information Technology P.O.Box 12041 FI-02044 VTT Finland tel. +358 9 456 1 fax. +358 9 456 7052 email: asta.back@vtt.fi, sari.vainikainen@vtt.fi, caj.sodergard@vtt.fi, helene.juhola@vtt.fi Knowledge management is a big challenge especially in large organisations. Knowledge resides in many different forms: as explicit knowledge in documents and processes and as tacit knowledge in people and procedures and in many different forms between these two extremes. The vision of the Semantic Web is to offer more intelligent services by facilitating machine understanding of web content. Ontologies are an important building block in Semantic Web. An ontology describes the concepts, their relationships and properties within their domain, and it can be utilised both to offer automatic infering and interoperability between applications. This is an appropriate vision for knowledge management, too. This paper describes how Semantic Web ontologies can be utilised in a research organisation to create a common language to describe its knowledge. The same ontology can be utilised to manage projects, people, documents and products. With a common ontology, information that is spread out in many different applications and documents can be viewable in a way that is easy to understand and navigate. The ontology makes it possible to search both knowledge content and experts who are linked to different topics, thereby bridging the gap between the tacit and explicit knowledge. INTRODUCTION Knowledge management is a big challenge especially in large organisations. Knowledge resides in many different forms: as explicit knowledge in documents and processes and as tacit knowledge in people and procedures and in many different forms between these two extremes. When an organisation wants to improve its knowledge management, it is important to focus is on strategically important knowledge. It is also important to clarify, how the organisation understands and defines knowledge. In [1], six different ways to define knowledge are listed. They are knowledge as personalised information, state of mind, object, process, access to information and capability. And there are even other definitions, such as knowledge as an asset. The best ways to manage knowledge depends naturally on which view on knowledge is taken, and then to choose the methods accordingly. There are many ways to view on the knowledge management process [2], the following five steps are often identified: 1. acquisition 2. creation, 3. storage, 4. validation, and 5. utilisation. The vision of the Semantic Web is to offer more intelligent services by facilitating machine understanding of content. Ontologies are an important building block in the future Semantic Web. Ontologies provide a shared and common understanding of a domain that can be communicated across people and applications. This is an appropriate vision for knowledge management, too. Originally, Ontology is a branch of philosophy that deals with the theory of being and considers questions about what is and what is not. In information technology, an ontology is the working model of entities and interactions in some particular domain of knowledge or practices, such as electronic commerce. In artificial intelligence (AI), an ontology is, according to Tom Gruber, an AI specialist at Stanford University, "the specification of conceptualizations, used to help programs and humans share knowledge." This seems to be one of the most, or even the most quoted definition for an ontology. In this meaning, an ontology consists of specified concepts that are defined to create an agreed-upon vocabulary for information exchange. Knowledge in ontologies is mainly formalised using five kinds of components: classes, relations, functions, axioms and instances. [3] Ontologies themselves can be classified into the following groups: • Knowledge Representation ontologies • General/Common ontologies • Meta-ontologies, also called Generic Ontologies or Core Ontologies • Domain ontologies • Task ontologies