“二阶抽样”的概念、定义、翻译、参考文献-科学参考

单词	二阶抽样
释义	二阶抽样 Encyclopedia 农学抽样调查释 two-stage sampling二阶抽样设总体由个初级单元组成，每个初级单元又由若干次级单元组成，在总体中按一定方法抽取若干初级单元，对每个被抽中的初级单元再抽取若干次级单元进行调查的方法。
随便看	gas porosity gas power cycles Gaspra gas-pressure gas pressure of coal seams gas pressure regulator gas pressure sintering of ceramics gas pressure welding car gas producer gas production engineering gas production per unit pressure drop gas production process of gas storage gas production rate gas productivity index gas property parameter in high pressure gas pseudo pressure gas purification method gas purification process gas quality standard for transmission pipeline gas radiative properties gas reaction system gas recirculation fan gas recovery by liquid drainage gas regulator station gas reservoir

科学参考收录了854744条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。