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- Application of stratum sampling to classification of RS image. 应用分层采样技术进行大面积遥感图像分类的研究
- By trench observations and dating of fault rocks and stratum samples, it is proved that the fault has dislocated the stratum of middle Pleistocene. 经系列探槽的开挖，断层构造岩及有关地层样品作绝对年龄测定，证明东岗断层错断了中更新世地层；
- The Role and Function of Modified Strata Sampling in the Working Statistical Investigation System 划类选点抽样调查方法在现阶段统计调查方法中的地位和作用
- Keywords run-through DTH;chip removal by reverse circulation complex strata sampling bit;air jet drilling; 贯通式潜孔锤;反循环排屑;复杂地层;空气喷射钻进;
- We can follow the history of life through the strata. 我们可以通过这一层层的地层跟踪生命的历史。
- strata sampling 分层抽样
- They represent each society stratum. 他们代表各个社会阶层。
- I spent a few days sampling the literature of social science. 我花了几天时间浏览有关社会科学的文献。
- The older strata gradually disintegrate. 较老的岩层渐渐风化。
- The older strata gradually disintegrated. 年代较久的地层逐渐崩解了。
- stratum sampling 分层抽样
- They do not constitute a separate class or stratum. 知识分子和青年学生并不是一个阶级或阶层。
- These strata, lying apparently in contact, are in fact abysmally separated. 这些表面上相触的地层实际上相隔很远。
- It involves a subject known as isokinetic sampling. 这涉及所谓等速取样的问题。
- To expose(rock strata)by erosion. 剥蚀因腐蚀而露出（石层）
- He hates the privileged stratum. 他憎恨特权阶层。
- The concept of sampling will be presented below. 关于采样的概念，后面将要说明。
- They belong to the rich strata and never work. 他们属于富裕阶层，不干活。
- There are many applications for random sampling. 随机抽样有许多应用场合。
- They represent all social strata . 他们代表各个社会阶层。
