中文摘要：

模糊合成算子是模糊数据处理的核心技术。目前，在模糊评价中模糊算子的应用混乱，没有一般的方法可循。原因之一是扎德的模糊数学理论存在缺陷，另一方面是对算子的性质和数据的研究不够。清晰域是模糊合成算子的重要性质，在清晰域内的数据，计算结果是确定的，不具有模糊性，而在清晰域之外的数据有效。雅戈尔算子是参数算子，清晰域是变化的。研究了雅戈尔清晰域，它的大小是随参数增大而递减的；为了使清晰域不包含任何数据点，推导出了确定雅戈尔参数的计算公式，给出了雅戈尔算子在模糊评价中的应用方法，充分发挥数据的作用，用算例验证了这个方法的有效性。

英文摘要：

Fuzzy composite operators are the core technique of data processing in the fuzzy evalua- tion. At present, the applications of fuzzy operator are confusing in fuzzy evaluation, and there is not a general method. One reason is the shortcoming of Zadeh＇s fuzzy set theory. On the other hand, the re- searches of the operation property are not enough. Clear field is an important property of fuzzy composite operators. In clear field the data calculation results are sure, are not fuzzy, but outside clear field the da- ta is effective. Yager operates are the parameter operators, having the change clear field. Clear field of the Yager operators is considered and it is shown that the clear field gets smaller as the parameters get bigger. In order to no data point is included in clear field, the formula of calculating Yager parameters is deduced, and the application method of Yager operators in fuzzy evaluation is given. An example presents the effectiveness of the method.