首先，本文简单介绍了几种随机模拟方法，并对重要性抽样作了改进，从而为选取好的重要函数提供了方法和理论依据。

First, some random simulations are introduced and the important sample is improved, which supplies the method and theory for the choice of the important sample.

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具体介绍了砼强度检测抽样的几种方法：现行规程抽样法；简单随机抽样法；分层抽样法。

This paper introduced several methods about the concrete strength inspection: the sampling method given by the present specification; simple random sampling without replacement; stratified sampling.

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