查询词典 sampling

Among probability sampling methods, what kinds of research conditions are more appropriate for each sampling method

什麼样的情况下，适合用机率抽样方法简单随机抽样有4种方法：1。简单随机抽样2。分层随机抽样3。系统抽样等距抽样

Students will learn Descriptive Statistics, Probability and Random Variables, Probability Distributions, Sampling and Sampling Distributions in Statistics.

同学们将在统计学中学习叙述统计量的意义与计算、机率与随机变数、机率分配、抽样与抽样分配等基础统计方法。

Besides correct sampling procedures, proper sampling frequency is necessary to monitor the oil condition and the wear trends of machinery components.

除了要保证正确的取样程序外，合适的取样频率也是检查润滑油状况及设备零件的磨损趋势所必须的。

Besides correct sampling procedures, proper sampling frequency is necessary to monitor the oil condition and the wear trends of machinery component s.

除了要保证正确的取样程序外，合适的取样频率也是检查润滑油状况及设备零件的磨损趋势所必须的。

Besides correct sampling procedures, proper sampling frequency is necessary to monitor the oil condition and the wear trend s of machinery components.

除了要保证正确的取样程序外，合适的取样频率也是检查润滑油状况及设备零件的磨损趋势所必须的。

Methods Population Proportional to Size sampling method was employed in sampling.

方法2005年11~12月采用分层、三阶段与规模成正比的容量比例抽样方法获得调查对象，采用统一调查问卷由统一培训的调查员入户进行面对面调查。

Methods The multi stratified grouping random sampling method and the proportional sampling was used.

本次流调方法与全国第四次流调方法基本一致，采用分层整群等比例随机抽样方法。

Small signal equivalent circuit analysis shows that the small signal output resistance in the accurate proportional current sampling mode circuit is much larger than that in a traditional proportional current sampling mode circuit, and circuit stability could be assured.

通过电路的小信号模型分析，得到精密比例采样模式的小信号等效输出电阻远大于传统比例采样模式，同时保证了系统的稳定性。

Circuit simulation and chip testing results show that when the LED driving current is 350 mA and the power supply is 6 V with ±10% variation, the stability of the output constant current of the accurate proportional current sampling mode LED driving IC will show 41% improvement over that of a traditional proportional current sampling mode LED driving IC.

经电路仿真及流片测试，表明当LED驱动电流为350mA，电源电压6V并正负波动10%时，改进的精密比例采样模式LED驱动电路比传统比例采样模式LED驱动电路的恒流特性稳定度提高了41%。

Because there were many occasional species in the desert and the distribution of many species were dependent largely on the habitat, the paper concluded that neither the methods of sampling line and nest method for all species nor the sampling method of the pattern of plum blossom quadrat for the herbaceous species could be suitable for observation in the desert.

由于沙漠物种偶见种多，频度和密度较低，并且分布的环境特异性强，认为对沙漠植物群落观测，样线法、巢式样方法以及对草本观测的梅花样方法均具有一定局限性，建议对草本和灌木物种多样性观测，在确定合理的布样方向基础上，以4m 4m为基本样方。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。