Knowledge Engineering

The discipline of knowledge engineering grew out of the early work on expert systems in the seventies. With the growing popularity of knowledge-based systems (as these were by then called), there arose also a need for a systematic approach for building such systems, similar to methodologies in main-stream software engineering. Over the years, the discipline of knowledge engineering has evolved into the development of theory, methods and tools for developing knowledge-intensive applications. In other words, it provides guidance about when and how to apply particular knowledgepresentation techniques for solving particular problems. In this chapter we first discuss (Section 25.2) a number of principles, that have become the baseline of modern knowledge engineering. These include the common distinction made in knowledge engineering between task knowledge and domain knowledge. In Section 25.3 we explore the notion of problem-solving tasks in detail and present typical patterns and methods user for solving such tasks. In Section 25.4 we focus on the domain perspective, in particular the representation and use of ontologies. Finally, Section 25.5 summarizes the main techniques that are being used in knowledge engineering, examples of their use.