A design language and the use of cleanroom methodology for knowledge-based system development

Abstract

In an effort to improve the quality of knowledge-based systems, use of the Cleanroom Software Engineering Methodology was explored. the methodology emphasizes the use of stepwise refinement techniques and proofs of correctness to prevent errors early in the development process. This calls for the use of a well-defined design language and verification techniques to prove the correctness of the design. But practical design languages and verification methods for knowledge-based systems are not well understood. This article discusses a design language, associated verification techniques, and experience with their use in developing a knowledge-based system. the language is an extension of procedural design languages with representations for control and opportunistic knowledge, emphasizing typical knowledge-based programming ideas and ease of verification. It is intended for use with a stepwise refinement process that iteratively develops detailed designs from high-level specifications. the extensive use of structured English language specifications throughout the process makes the approach practical but limits the ability to verify designs using automated tools. the design language and associated processes were used in the development of a prototype flight replanner for future air traffic control systems—a large and complex application of knowledge-based technology. © 1994 John Wiley & Sons, Inc.