Evaluation on ambiguity of human factor by fluctuation of membership function

This paper deals with the human error induced by the ambiguity of multijudgement process to complete a mission. By using a plant model, the authors tried to evaluate the ambiguity of operators, and to establish the model for simulation. Through the comparison of the behavior of actual operators and simulators, the ambiguity could be identified with same parameters. Fluctuation of values of a membership function on a particular relation was introduced, and evaluated through the comparison above-mentioned. The authors found that the degrees of fluctuation, that is, the ambiguity of individuals is different, and is related to design error as well as operation errors induced by multijudgement process