Rating and Ranking Versus Compliance Analysis: Defuzzification Techniques for Conceptual Design Evaluation
Caroline Smith and Dinesh Verma
Structure and discipline during the conceptual design phase are fundamental to the efficient and effective development of competitive products and systems. However, the extent and resolution of information available during this phase, in the form of parameter values and priorities, is characterized by imprecision and subjectivity and well represented by fuzzy variables and linguistic values. Discrimination between competing product concepts must be made within such a framework. One key element of applying multi-valued logic techniques to product concept evaluation and differentiation is the identification of a defuzzification technique. Existing defuzzification techniques are based on the philosophy of rating and ranking fuzzy sets. This paper argues that a defuzzification technique based on compliance between required and anticipated parameter values is more suited to concept evaluation and selection. The advantage of such an approach is demonstrated. Finally, techniques for accelerating such a compliance analysis are suggested.