Order structure of fuzzy numbers based on rules

Evolutionary algorithms and fuzzy techniques have been proven to be powerful tools used for intelligent computations. How to organically combine their strong points becomes urgent for many practical problems, such as production line scheduling in complex manufacturing systems, and this is also greatly concerned in academia. In this paper, after setting forth the current situations of evolutionary algorithms and fuzzy techniques, we give a way ranking fuzzy numbers by use of the location values of fuzzy numbers based on a rule pool and the metric on the fuzzy number space. The term of coincidence degrees is then introduced to reflect the degree of correlation about a fuzzy number with a given rule pool. Furthermore, some basic properties for location values are considered, and techniques for computing location values in terms of some special metrics are also presented. All these will offer a basis for further researches about the theory of evolutionary computations under uncertain environments.