中文摘要：

为了解DSFT概念下的因素投影拟合法得到的元件故障概率空间分布与CSFT所得的相对准确的分布存在较大差别的原因，即分析原有因素投影拟合法的不精确原因，论文重新分析了该方法的计算过程．发现元件关于使用时间t和使用温度c的特征函数Pit（t）和Pic（c）的确定是不准确的．对这两个函数进行了重新构建，通过一系列推导得到了特征函数的新表达式．对比分析表明：原方法得到的函数线型与真实结果是形同的，只是缩放程度和平移量不同，所以仍有实际的借鉴意义．c0和t0作为自变量形成了一组函数族，但由于缺少约束条件仍无法具体确定数值．

英文摘要：

In order to understand the bigger difference reason between the failure probability spatial distribution by factors projection fitting method in DSFT and relatively accurate result by CSFT, the calculating process of this method is analyzed again to understand the reasons of the imprecision. It is found that the determination of the characteristic functions P[（t） and P[（c） of working time t and working temperature e is not accurate. To rebuild these two functions, the new expressions of the characteristic functions were obtained through a series of derivation. Contrast analysis shows that the function linear of the method is the same as the real result, except degree of scaling and translation quantity, so there is still practical significance, co and to as independent variables to form a group of family function, but because of the lack of constraints, co and to are still unable to determine the specific numerical value.