国外一篇文献上有关于检测极限的测定方法,文章上用英文这样说的: "Method detection limit was determined by selecting the standard concentration which was slightly higher than the low concentration of the standard line, the process was repeated twelve times to estimate the standard deviation(S). The MDL was determined to be (3*S)." 这句话我有点看不懂,还请高手指点翻译,谢谢!