线性的

The existence condition of first and second boundary variation was given with boundary variation method. The numerical method was obtained.

应用测度理论，将经典的变分问题，利用线性分析的方法转化为在几个Randon测度空间中寻找最优测度的有限维线性优化问题；从而得到最优控制律。

Symmetry group is semisimple, the system has a fine cascade decomposition that is a qasi-parallel decomposition, which is corresponding to the decomposition of linear systems under the semisimple symmetry algebra.

由于对称代数对线性系统的结构有重要作用，特别是当该代数半单时，系统可分解为多个独立的子系统，因此如何就给定的线性控制系统构造出其对称代数具有重要意义。

As we have been known, Electro-hydraulic servo-system is essentially non-linear, and using the traditional operational-point linearization approach to devise controller, the effect of controlling relies on the precision of linearization and the operational point where it is.

电液伺服系统是本质的非线性系统已经为人们所共识，在用传统的工作点线性化方法设计控制器时，控制效果依赖于线性化精度和所在的工作点。

According to the computational stability analysis conducted to the linear term time difference scheme in simple harmonic motion equation, one new semi-implicit integration scheme also is designed. By adopting a kind of revised time-explicitdifference scheme to these linear terms still included in spectral model governing equations, this defect of spectral model only partly used in semi-implicit integrating scheme, can be overcome to some degree.

以简谐振动方程中线性项时间差分格式对其计算稳定性影响为理论依据，本文设计了一种新谱模式半隐式时间积分方案，此方案通过对一般谱模式求解框架中那些隐含的线性项采用了一种显式修正的差分格式，可有效克服其国际谱模式半隐式时间求积方案实质上只是部分应用了半隐式差分格式的问题。

Discussion topics include data analysis, probability concepts, point and interval estimation, statistical inference, hypothesis testing, simple regression model, inference in the simple regression model, general linear statistical model, dummy variables, collinearity, heteroscasticity, autocorrelation, error-related model, the Probit model, the Logit model and the Tobit model, simultaneous equations, and the time-series statistical model

讨论的主题包括实证资料的分析，机率，点估计与区间估计，统计推论，假设检定，简单回归分析，一般线性统计模型与推论，虚拟变数，共线性问题，异质变异数，自我相关， Probit模型， Logit与Tobit模型，联立方程式的估计与推论，时间数列统计模型。

First, various normwise relative condition numbers that measure the sensitivity of W-weighted Drazin inverse and the solution of singular linear systems are characterized.

首先，我们利用不同的范数定义了加权Drazin逆及其奇异线性方程组解的条件数，用来度量矩阵求加权Drazin逆和一类奇异线性方程组求加权Drazin逆解对于扰动的敏感性。

When a discussion is made on the blow-up problem for a semilinear development equation with singular cofficient,the solution is usually estimated,then the conditions for the blow-up problem are presented.

讨论奇异半线性发展方程组解的B low-up问题时，通常先对解进行估计，然后讨论在一定条件下解的B low-up。论文继续用这种方法讨论奇异半线性发展方程组解的B low-up问题，得到一定条件下解会B low-up

This paper analysised and researched some existing algebra feature extraction method such as KL transformation, singular value decomposition、 Fisher linear discriminant and optimal discriminant transformation. On the base of this、we expound a method which named uncorrelated optimal discriminant transformation to accomplish the face recognition.Uncorrelated optimal discriminant transformation is a improvement of Fisher linear discriminant and optimal discriminant transformation.

本文对一些现有的代数特征提取方法如KL变换、奇异值分解、Fisher线性鉴别以及最佳鉴别变换做了分析和研究，在此基础上我们提出使用具有统计不相关最佳鉴别变换的投影方法来进行人脸识别，它是由Fisher线性鉴别和最佳鉴别变换改进、完善而来的。

In this paper, an algorithm to achieve both two dimensional high resolution and wide swath is proposed. Every small satellite work in the active state, they transmit and receive different frequency band signal simultaneity. First, the azimuth ambiguity is eliminated in each frequency sub-band, then the signal is rectified to zero Doppler frequency, after that this algorithm does the range spectral synthesis to achieve high range resolution.

该文分析了一种沿航向排列分布式小卫星宽测绘带二维高分辨率成像技术，每颗卫星同时发射接收不同频率的线性调频信号，先分别在每个子带解方位多普勒模糊，并将方位多普勒中心频率调整至零频，然后在距离向进行子带拼接得到大带宽的线性调频信号从而得到高的距离向分辨率。

Then, some criteria, i.e., the sufficient conditions, for the asymptotical stability of the system in form of mean square are given by linear matrix inequality, which can easily be checked by Matlab toolbox.

然后基于线性矩阵不等式技术，给出了时滞随机分布参数系统稳定的充分条件，所得到的结果表示成线性矩阵不等式的形式，所以易于验证。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。