查询词典 approximate differentiability

Apparently, the approximate controllability doesn"t hold for generally linear parabolic equations with bounded control. It doesn"t hold for the semilinear heat equations presented there,either. Then, it is proved by analyzing its" solutions that no matter how long the time T is , there are targets that can"t be approximated by the solution of heat equation with Dirichlet boundary conditions;If a given target satisying certain conditions can be reached by the solution of heat equation .

本文先针对两个具体的半线性热方程系统证明了控制加约束后系统是不能控的；然后通过分析方程的解，对带位势及Dirichlet边界条件的热方程系统，无论时间多大，都存在不能控的目标；文中还证明了满足一定条件的目标可达。

And the thesis is divided into 4 parts.In the first part, the development of technology on Adjustable Speed AC Dirve is introduced. And the theory of DTC is analyzed. Besides the two classic DTC strategy, the hexagon flux track and approximate circle flux track controlling system, the thesis introduces some DTC strategies modified and some new controlling arithmetics.

论文共分为四个部分：第一部分介绍了交流调速技术的发展，分析了异步电机直接转矩控制的基本原理，除六边形磁链和近似圆形磁链两种经典的DTC控制之外，还介绍了改进型DTC及其他新型的控制算法。

In Chapter Four, the original discrete series consisting of network traffic data is decomposed into approximate series and several detail series.

在第四章，首先将流量数据构成的原始序列进行小波分解，并将分解得到的近似部分和各细节部分分别单支重构到原级别上；其次对各个重构后的序列分别建立自回归模型，由所拟合的模型分别进行预测。

Finally, the characteristic of nonlinear TM waves propagating in five-layer nonlinear waveguide is analyzed elementarily. The approximate analytical solution is presented based on the characteristic of TM_0, the dispersion relations is given.

最后对非线性光波导中的TM模传输特性进行了初步的研究，利用TM_0模的特性，采取了一种近似方法初步分析非线性介质平板波导TM_0模的近似解，给出了色散关系式。

The purpose of this paper is therefore to present a approximate methol for calculating the load distribution coefficient of the girder shear force.

本文的目的在于提出计算主梁剪力荷载横向分布系数的近似方法，并用电算编制了设计用表。

But for the middle and large scale problems, the computation cost by symbolic differentiation is very expensive. When the direction derivative is evaluated, the computation cost by divided difference can be reduced, but it is only one kind of approximate computation.

对于大中规模问题来说，使用符号微分，成本昂贵，有时甚至不可行，在计算导数的方向梯度时，利用差分法虽然可以降低计算成本，但得到的是近似值，而且确定恰当的差分区间也很困难。

We use the Taylor series expansion method to get the second-order approximate expression of the confidence region of the parameters, and then according to the principle of minimizing the volume of the confidence region, this paper carries out experimental design for the regression model, and then fixes the point range in the domain of definition of design variable for the model function so as to select the designing point, which can minimize the volume of the confidence region.

文章首先计算指数族非线性模型的回归参数β在1-α置信水平下的置信域的体积，为了便于计算，需把置信域投影到切空间中去，投影后的置信域是一个椭球体，用Taylor展开方法对此椭球体的体积进行二阶近似，推出原参数置信域的体积的近似表达式，然后对回归模型进行试验设计，根据置信域体积最小准则，在模型函数的设计变量的定义域上确定点列，选取使置信域体积达到最小的设计点。

On the principle of both work and energy equalization during the upstroke and downstroke, the writer analyses an approximate calculating method of rotary balance acquired by this type of the beam pumping unit.

本文根据抽油机上下冲程功能相等的原则，分析了前置式抽油机取得旋转平衡的近似计算方法。

Chapter V, accordingly, concludes the attempts of the entire thesis: Sartre is inferior to Beckett in terms of dramaturgy although both of them present approximate existential ideas on stage.

第五章总结全文的论点。就呈现人类荒谬的存在状况而言，贝克特在「终局」之中的戏剧手法优於沙特的「没有出口」。

The influence of time on displacement was obtained, and the curve slope was approximate equal to drift velocity of electrons.

绘制了电子的位移与时间关系图，得到的曲线斜率可近似认为是漂移速度。

When this condition occurs, inbound replication with the source partner is stopped on the destination domain controller and event ID 2042 is logged in the Directory Services event log.

计算机密码学是研究计算机信息加密、解密及其变换的科学，是数学和计算机的交义学科，也是一门新兴的学科。

Instructions: click on the thumbnails to see a larger image, then use the left-right arrow keys to scroll through the slideshow.

使用说明：滑鼠点在小图上即可放大观赏。开启后键盘左右键可用来换照片。