抽样法

Methods A total of 852 children aged from 9 to 10 years were recruited with multi-stage sampling.

方法采用多阶段随机整群抽样法抽取852名北京市城区9～10岁学生。

This paper proposes Latin hypercube sampling combined with variance reduction techniques of conditional expectation and antithetic variates to assess ultimate strength reliability of ship hull girder.

本文将拉丁超立方抽样法与条件期望和对偶变数方差减缩技术组合用于分析船体总纵极限强度可靠性。

We give the expression and confidence interval for failure probability in direct sampling method .

本文讨论了蒙特卡洛模拟在结构可靠性分析中的应用，并给出了直接抽样法中失效概率的计算公式和置信区

Rats were administered intraperitoneally 30 min prior to reperfusion via Danshen served as Danshen Group and the rest were administered intraperitoneally via NS instead served as contrast group.6 rats with the left cremaster muscles open served as normal contrast group.

采用夹闭SD大鼠左侧提睾肌主滋养动脉法造模，将66只SD大鼠用随机抽样法抽出6只作为正常组，另外60只分为对照组和丹参组，每组各30只。

Under the higher-dimensional situation, it introduces mainly the multiple integrals formulas on some standard areas, the multiple integrals formula by the methods of sampling, the reduction of dimensions and the boundary type cubature with a certain algebraic precision, and calculate multiple integrals with the methods of number theoretical net and so on.

在高维情形下，主要介绍了一些标准区域上的多重积分公式，用抽样法来求多重积分，具有代数精度的降维展开式和边界型求积公式，以及用数论网格的方法来计算高维积分等。

Methods The patients were randomly divided into an acupotomy treatment group of 30 cases and an electrotherapy control group of 30 cases.

采用完全随机抽样法将观察病例分为针刀治疗组30例，电针对照组30例。

Our methodology is based on the fundamental principles of the phenomenology, hermeneutic and semeiology. For the samples in this study, the data were mainly collected by the purposefulness sampling, interview and inspection method of qualitative research.

在方法论上采用现象学、解释学和符号学的基本观点，在具体做法时采用质的研究方法中的目的性抽样法、访谈法和观察法收集资料。

Finaly, the reliability of static ice force for different reccurrence periods is calculated by taking Schwarz formula as formula of calculating static ice force and results are simulated by Monte Carlo important sampling method.

最后，以Schwarz公式为静冰力计算公式，结合得到的冰厚和冰强度的概率分布，采用映射变换法进行不同重现期静冰力的可靠度分析计算，并用蒙特卡罗重点抽样法进行模拟。

In March to middle of June of 2004,fifty random selected nests of Phalacrocorax carbo in Majuan Island of Sanjiang National Nature Reserve of Haiqing town of Fuyuan county of Heilongjiang province were numbered and measured one by one to study the materials,location and direction,and size of the nests.

2004年3~6月，在黑龙江省三江国家级自然保护区海青保护站马圈岛，采用随机抽样法，对随机选取的50个普通鸬鹚巢逐一进行编号和测量，进行巢材、巢位和巢大小等的研究；采用总面积调查法(样方大小为30m×30m)，对普通鸬鹚巢的分布格局、分布特点进行了研究。

Six field study sites including Limu Mountain, Jianfengling Mountain, Bawangling Mountain, Nanmao Mountain, Ewanling Mountain and upper researches of Wenjiao River were investigated by regular sampling and cage trapping.

对18个市县的103个乡镇进行了走访调查；野外调查中采用系统抽样法和笼捕法，对黎母山、尖峰岭、霸王岭、南茂岭、万俄岭和文教河上游6个研究点进行了调查。

By the time of its fall, most of the prisoners were writers who had written against the corruptions of the government.

到它被攻陷的时候，里面多数的犯人是写了反对政府贪污文章的作家。

The most obvious variation to ovum morphological character was that the color was changed from light green to sepiaceous in embryonic development, and all the ovums were almost hatched after 96h.

在胚胎发育过程中卵的形态特征最明显的变化是颜色从淡绿到深褐色，卵在发育96h后卵基本全部孵化。