In this paper I introduce a knowledge-based analysis system, called the fuzzy reasoning system (FRS), as a design analysis and evaluation tool. The FRS consists of fuzzy reasoning charts (FRCs) and fuzzy reasoning equations (FREs). The FRCs depict design-related knowledge with networks of nodes and mappings representing design issues and their interactive relations. The FREs implement the networks in a computational form that operates, according to the specified relations, on the status measures of the issues. This system offers a medium for explicitly specifying and communicating design knowledge, opinions, and requirements. It could help designers to maintain consistency, examiners to assess designs, and decisionmakers to analyze alternatives. It could also form a subsystem in an integrated CAD system dealing with both evaluation and composition, the two fundamental components in a design process. With an example of construction design, I will also demonstrate the implementation of an FRS on a microcomputer.
