Abstract: The ranking of fuzzy numbers occupies a very important position in the problems of decision analysis and optimization, and a fuzzy number can be approximately decomposed into several small shard trapezoidal form of superposition. Therefore, the ranking problem of trapezoidal fuzzy number is very important. In this paper, a trapezoidal fuzzy number can be implemented in a vertical lengthways segmentation along the axis-y through introducing the method of equidistant subdivision, and an ordered expression of the trapezoidal fuzzy number may be obtained. Secondly, according to the center weighted average rule the horizontal and vertical center formula of a trapezoidal fuzzy number is improved, and a new index ranking criterion is put forward. Finally, we verify the effectiveness of the new ranking method through an example analysis.

Key words: trapezoidal fuzzy number, equidistant subdivision, ordered expression, center coordinates, index ranking criterion

摘要： 模糊数的排序在决策分析和优化问题中占有十分重要的地位,而一般模糊数均可近似分解为若干分片小梯形的叠加形式,故梯形模糊数的排序问题至关重要!本文首先引入等距分片方法对梯形模糊数实施纵向分割,进而获得梯形模糊数的有序表示。其次,依中心平均加权准则改进梯形模糊数的横向和纵向中心坐标公式,并提出新的指标排序准则。最后,通过实例分析考证了新的排序方法的有效性。

关键词: 梯形模糊数, 等距分片, 有序表示, 中心坐标, 指标排序准则