first-order second moment

基本解釋

Based on First-order Second-moment Method(FOSM), a formula for calculating t.
在一次二階矩法的基礎上，推導了計算模糊隨機可靠度的具體公式。
The level of environmental risk can be transformed into ordinary probabilistic environmental risk and computed using advanced first-order second-moment method.
最后，將具有灰色概率形式的環(huán)境風險度轉(zhuǎn)化成一般的系統(tǒng)失效風險率，進而用改進一階二矩法進行計算。
In reliability analysis for tunnel lining structure, the simple first-order second-moment method combined with stochastic finite element method is usually employed, but its precision is low.
雖然有很多高精度的結(jié)構(gòu)可靠度分析方法，但大多太復雜或計算時間長，不適用于隧道結(jié)構(gòu)的可靠度計算。