Simple computation for the defuzzifications of center of sum and center of gravity

Authors:
Wen-June Wang;Leh Luoh
Affiliations:
(Correspd. Fax&colon/ +886 3 4255830&semi/ E-mail&colon/ wjwang@csie.ncu.edu.tw) Department of Electrical Engineering, National Central University, Chung-Li 320, Taiwan, ROC;Department of Electrical Engineering, National Central University, Chung-Li 320, Taiwan, ROC
Venue:
Journal of Intelligent & Fuzzy Systems: Applications in Engineering and Technology
Year:
2000

Citing 0
Cited 5

A Study on the Evolutionary Adaptive Defuzzification Methods in Fuzzy Modeling

International Journal of Hybrid Intelligent Systems
Centroid defuzzification and the maximizing set and minimizing set ranking based on alpha level sets

Computers and Industrial Engineering
Fast and accurate center of gravity defuzzification of fuzzy system outputs defined on trapezoidal fuzzy partitions

Fuzzy Sets and Systems
Parameterized defuzzification with maximum entropy weighting function-Another view of the weighting function expectation method

Mathematical and Computer Modelling: An International Journal
An integrated expert system for fast disaster assessment

Computers and Operations Research

Quantified Score

Hi-index	0.00

Visualization

Abstract

In most inference engines, the output of a fuzzy rule base before defuzzifying is the union of some trapezoidal or/and triangular fuzzy sets and it is always of irregular shape. The defuzzification by using the "center of sum" (COS) method or the "center of gravity" (COG) method for the irregular fuzzy set is then a troublesome computation because of some integrations. This paper proposes two formulas to compute the center of gravity of triangular and trapezoidal fuzzy sets respectively. Based on the proposed two formulas, the computation of COS defuzzification for an irregular fuzzy set can be simplified to a weighted average of the gravities of the trapezoidal or/and triangular fuzzy sets. An example is illustrated to show that the computation time of the pre-defuzzification method with the proposed formula is much less than that of the commonly used COS and COG defuzzification method.