查询词典 computation errors

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。

The computation by using image coordinates will cause computational breakdown or deterioration of accuracy when they become too large,and the computation by using homogeneous coordinates will increase computation work.

现在，越来越多的人们逐渐把注意力放在关于射影几何的计算以及利用不变量进行物体识别[3][4]。

Therefore, it is necessary to test the computation results and further modify the computation method based on the comparison between the numerical solution of the linear or non-linear equations and the trial value or the computation results of typical cases.

所以，需依靠对非线性数学方程的数值实验及数值解与试验或典型算例结果的比较和物理特性分析，验证数值计算结果，进一步改进计算方法。

Some new method is presented in this paper: A. An Integrated parameters computation method to analysis asynchronous operation of the turbine generator is given, including the equivalence of short circuit and open circuit of field windings, deducing boundary condition of 〓 method and computing frequency parameters. B. A new memory structure for sparse complex matrix and a PCCG method based on it are introduced to save memory and computation time. C. An equivalent method of vacuum is presented, and effectively eliminate the effect of corner point and accelerate convergence of PCCG method. D. Coupling the computation of electromagnetic and temperature field is discussed and model for computing temperature field of the turbine generator rotor at asynchronous operation is built.

文中提出了以下新方法：(1)在失磁异步运行转子三维涡流场计算中提出了完整的参数计算方法，其中包括励磁绕组开、短路的等效，〓法边界条件的推导及频率参数的计算方法；(2)提出了铁心内空气域的等效方法，有效地解决了开槽引起的角点奇异问题，并提高了方程组的迭代收敛速度；(3)在〓法有限元模型中，创立了一种能节约内存、提高计算速度的压缩存储矩阵格式，并建立了基于该格式的方程组解法；(4)提出了涡流电磁场和温度场两种不同场计算的合理结合方法，建立了转子三维稳态和时变温度场的有限元计算模型。

Among them, the first main part is the selection of material parameters, and it has great effect on the validity of the computation result. The second part is predigestion of geologic model and mechanics model adopted. Compared with the two factors above, computation method adopted has less effect on computation result, but sometimes, it is very important for some special problem such as localization shearing damage.

其中，力学参数的选取是第一位的，对计算结果的正确与否影响最大；其次是地质模型的简化及所采用的力学模型；所采用的计算方法对计算结果的影响与前两个因素相比虽然较小，但对某些特殊问题有时又非常重要。

The choice of the electric motor, the design of the band pulley, the design of the axis structural, the examination of the axis intensity, the choice computation of the keying, the choice of the rolling bearing type and code, the life computation of the bearing, the choice computation of the shaft, the choice of the lubrication and seal are carried on.

进行了电动机的选择、带轮的设计、轴的结构设计、轴的强度校核、键连接的选择计算、滚动轴承的类型代号选择、轴承的寿命计算、联轴器的选择计算、润滑密封的选择。

In the improved algorithm, the computation of three-order time derivative is replaced by convolution approximate calculation, which simplifies the computation process and reduces computation amount, and is high effective and robust.

改进算法用褶积近似运算代替时间3阶导数的求解，因此简化了计算过程，减少了计算量，是一种高效稳健的算法。

The traditional Givens rotation algorithm involves root computation which need more hardware resources, the paper presents a Givens rotation algorithm without root and division computation, combined with the special structure of the input signal matrix, a interference suppression algorithm with low computation is also proposed.

传统Givens旋转算法涉及到平方根运算，这种运算要消耗较多硬件资源或需要多次循环来实现，文中给出一种无平方根与除法运算的Givens旋转算法，并结合信号输入矩阵的特殊结构，给出一种低复杂度的干扰抑制算法。

The technological design computation uses the Aspen plus software , according to parameters and so on absorption system's system nature, is absorbed component separation purity, operating condition, carries on the material balance, the thermal graduated arm to the endoergic process to calculate, the mass transfer computation and so on, determined needs the padding level altitude, and carries on the optimized analysis and the computation.

工艺设计计算利用Aspen plus软件，根据吸收系统的物系性质、被吸收组分分离纯度、操作条件等参数，对吸收过程进行物料衡算、热量衡算，传质计算等，确定所需填料层高度，并进行优化分析与计算。

By definition,for targets located in a spherically stratified lower atmosphere or ionosphere,this paper derives the residual error models［Formulae (14) and (20);(24) and (27);(57) and (59),(63) and (65)］ of elevation angle refraction errors,range refraction errors and range rate refraction errors corresponding to monopulse radar and trilateration radar.

提要 本文从定义出发，推导出目标在球面分层低层大气或电离层内仰角折射误差、距离折射误差和相应于单脉冲雷达与三站雷达的距离变化率折射误差的残差模型［式(14)与(20)；(24)与(27)；(57)与(59)，(63)与(65)］。

Fostering the concept of multi-culture firmly and mastering the development of advanced culture correctly are conductive to resisting terrorism, separatism of nationalities and ultraism of religion, which is of great academic theoretical, immediate and profound historical si...

牢固树立多元文化的理念和正确把握先进文化的发展方向，有助于在世界范围内自觉地抵制恐怖主义，民族分裂主义和宗教极端主义。不仅具有重大的学术理论意义，而且也具有重大的现实意义和深远的历史意义。

But if anyone walks in the night, he stumbles, because the light is not in him.

11：10 若在黑夜行走，就必碰跌，因为那光不在他里面。