查询词典 sampling

According to the characteristics presented by armed helicopters during cruising or searching for ground targets, this paper has established the mean-square deviation stationary random model of helicopter tracks. It is an important method to decorrelate the measure noise by estimating the parameters of the color noise online. Kalman filtering and forecasting have been made with helicopter tracks. The simulated study has been carried out on helicopter tracks under the condition of color noise. It is very difficult to get an accurate and reliable prediction when the data is very limited. The paper make use of the theory of grey system to resolve the problem of prediction of helicopter tracks, establishing the GM model of grey systems and the cumulative residual error model of n degree, then correcting the GM forecast model. In the period of sampling, GM model and residual error model have been established on line to improve prediction precision.

结合武装直升机在巡航或搜索地面目标的特点，给出直升机航迹模型为协方差平稳随机模型，在线估计有色噪声参数，对测量噪声去相关，对直升机航迹进行卡尔曼滤波与预估，最后对有色噪声条件下的航迹进行了仿真研究；在数据非常有限的情况下，准确地预测又很困难，本文提出了用灰色系统理论解决直升机航迹预测问题，建立了灰色系统GM预测模型和n次累加残差模型并对GM预测模型进行修正，在每个采样期间内，实时在线建立GM预测模型和残差模型以提高预测精度。

Because of random sampling error, it is impossible to learn the exact value of b using only the information in the sample.

由于随机取样误差的存在，我们不可能通过样本知道b 的准确值。

The relationship between the estimated random sampling variance and the number of samples taken was studied.

本文对随机取样方差估计值的精度与样本数目之间的关系进行了研究，提出了相应的理论公式。

Sampling is done in one of three ways: Entire Population, Random Sample, or Both .

采样是在做一个三种方式：全部人口，以随机抽样方式选出，或两者兼而有之。

Methods Methods random sampling of patients will be divided into two groups of 130 cases.

采用随机抽样法将患者分成两组，每组130例。

Methods Using random sampling method,the patients were divided into two groups and each group had 25 cases.

采用随机抽样法将患者分成两组，每组25例。

Methods:1 109 cases of elderly people were investigated by a random sampling procedure.

采用随机抽样的方法，对深圳市1 109例老年人进行了生活质量调查分析。

Methods:2502 residents above 15 years old were selected and studied through random sampling methods in Beijing.

采用随机抽样方法对北京市人口15岁以上的2502人进行流行病学调查。

Methods Individual interviews and random sampling method was applied.

采用个别访谈和随机抽样的方法。

Methods Stratified random sampling method was adopted to select 4077 peasant workers from 10 enterprises to conduct questionnaire survey.

采用分层随机抽样的方法对10家企业4077名农民工的职业危害相关知识进行问卷调查。

"Second Life is remarkably easy to work with, and is very popular,"

"第二次生命是显着容易的工作，并且很受欢迎，"

For example, we usually assume that materials are homogeneous and isotropic and free of internal defects or flaws.

为了得到适合有限元分析的模型，我们必须经过如图2所示的简化步骤。