average life span

基本解释

The parties he formed, like all Korean parties (in P.J. O’Rourke’s words) had “the average life-span of a trout-stream mayfly hatch”.
他组建的政党，像其他韩国政党一样，用P.J. O’Rourke的话说,“其平均寿命就像鳟鱼溪里一只蜉蝣的孵化时间”。
This paper gives two methods to determine average life-span of steel products: weighted average method (WAM) and graphic shifting method (GSM) .
本文提出了两种确定钢铁产品平均使用寿命的确定方法：“加权平均法”和“曲线平移法”。
The average life-span of steel products in USA determined by GSM is 24 years in this paper.
采用曲线平移法，确定了美国钢铁产品平均使用寿命为24年。