REPRESENTING CK THEORY WITH AN ACTION LOGIC

CK theory is an interesting and unique theory of design. This paper introduces ALX3d, a formal version of CK based on the action logic ALX3, which is able to represent aspects of the actions, preferences, beliefs, and knowledge of collaborating, imperfect agents (such as human designers). It is shown that all the basic notions of CK can be rendered in the logic of ALX3d with only one relatively minor change in how the CK terms concept and knowledge are defined and related. Beyond this, ALX3d provides a richer framework for describing design activities in formal terms, including alternation between synthesis and analysis tasks, and the definition of goals that trade off design requirements against one another. A case study of CK from is used to show how ALX3d can also be used to describe some “real-world ” situations. The advantages of ALX3d are that they recast CK in a form more readily understood by those accustomed to expert, knowledge-based, and formal systems; provide a “scientific ” vehicle for reasoning about the design activities it can describe; and define a possible basis for the development of new, computer-based designers ’ aids