查询词典 necessary

Is it necessary to respect one's betters?

尊敬长辈有必要吗？

Bettina said she is doing practical training here because she is a graduate student. Her major is sociology. She said practical training is obligatory for them in their course but not necessary abroad.

Bettina表示，会在大叶实习是因为她目前仍是一个主修社会学的研究生，而实习在他们的课程中是必修的一环，但是不一定要在国外实习。

With the education reform, it is necessary to construct a new relationship adapted to the times between teachers and students.

随着教育改革的不断深入，建立与时代相适应的新型师生关系非常有必要。

Therefore, both the theoretical research and the practical application, it is very necessary to establish the basic theory of non-linear dynamics of spiral bevel gears and hypoid gear drives.

对于齿轮系统动力学的研究，不但可以分析和预测齿轮系统的振动和噪声，而且反过来也对齿轮的设计和加工提出了新的要求。

For most of us, diversification in love, at least beyond a very small number, is impossible, so it's necessary to do a lot of research on the choice you make.

对我们大多数人来说，在爱情方面多元化（即便是在一个极小的多元化数目）都是不可能的，因此有必要对你的选择做充分的研究。

For most of us,diversification in love, at least beyond a very small number, isimpossible, so it's necessary to do a lot of research on the choice youmake.

对我们大多数人而言，分散爱情的风险，是不可能的。

Beza traces it to a spontaneous, ie a natural and necessary, movement of the spirit, in which evil could not fail to spring up.

beza痕迹，它以一种自发的，即在一个自然和必要的，运动的精神，在这种邪恶的，可以不辜负春天到了。

Bianco suggests that the May4th movement represented the necessary first step towards a true social revolution.

Bianco提出"五四运动"是促成真正社会革命必需的第一步。

We first state general linear model, ridge-type estimator and general ridge-type estimator, and the constraint biased estimator. And then, we introduce some basic theory about matrix and some conclusion about the admissibility of estimator in Gauss-Markov model. In the third chapter, we discussion several equivalent characterization of the best linear unbiased estimation, we proved that admissible characterization of admissible of linear estimation is as conditional general ridge-type estimation in general linear model. A necessary and sufficient condition that homogeneous linear estimator is admissible estimator is obtained.

本文首先概述了一般线性模型，岭估计及约束岭估计的发展历史和研究现状，在第二章介绍了矩阵的一些基本知识和可容许性的一些基本结论，第三章讨论了一般线性模型最佳线性无偏估计的几个等价条件，以及线性估计的可容许性特征，得到了一般线性模型的可容许线性估计均具有条件广义岭估计的形式，给出了一个齐次线性估计为可容许估计的充分必要条件。

And then some ellipses that AUGR estimator is better than the OLS estimator and AUGL estimator is better than the OLS estimator are given, respectively.Second, the definition of the almost unbiased unified biased estimator is proposed. This definition includes the familiar almost unbiased estimators in literatures, and it is the unified expression of the familiar almost unbiased estimators. Followed the biased and variance are compared of AUUB estimator and the unified biased estimator, respectively. AUUB estimator has smaller bias than UB estimator and the variance of AUUB estimator is between the variance of UB estimator and 4 times of the variance of UB estimator. Finally the properties of AUUB estimator are discussed. The conclusion is gained that there are parameters made AUUB estimator is better than OLS estimator in terms of their mean square error. The sufficient and necessary condition that AUUB estimator is admissible is given. The ellipse is given that AUUB estimator is

然后给出了几乎无偏统一有偏估计的定义，该定义包括了文献中常见的几乎无偏估计，实现了常见几乎无偏估计的统一表达式；接下来我们比较了几乎无偏统一有偏估计与统一有偏估计的偏度与方差，得出了几乎无偏统一有偏估计比统一有偏估计有较小的偏度，几乎无偏统一有偏估计的方差介于统一有偏估计的方差与统一有偏估计的方差的四倍之间的结论；最后我们对统一有偏估计的主要性质作了讨论，证明了存在参数K，S使得几乎无偏统一有偏估计在均方误差意义下优于最小二乘估计的结论，给出了几乎无偏统一有偏估计为可容许估计的充要条件，还给出了在均方误差阵意义下几乎无偏统一有偏估计优于最小二乘估计的椭球。

The circulation, consumption and reproduction of the trilogy have not only testified to its historical significance and literariness, but also invested it with new meanings.

该三部曲的流通、消费与再生产不仅验证了其历史意义及文学性，而切还赋予它以新的意义。

If he thought that he could buy me off, he would be wrong.

如果他认为他可以收买我，那他就大错特错了。