系统误差

To evaluate the precision of solutions obtained by modal series method, normal form method and linear modal method, an error index describing the approximation to the nonlinear simulation is defined and then applied to the same system.

为比较模态级数法、正规形法和线性模式分析法所得解对时域仿真解的逼近程度，定义一误差指标，并在4机2区系统中做相关分析。

Based on practically stable principle, this paper extends the concept of sliding mode to sliding zone attraction and presents a new velocity observer for robotic tracking control It can guarantee observational error is irrelative to motion trajectory. By means of it, a robust controller is further derived.

本文基于实际稳定性原理，推广了滑动模控制，提出了滑动域吸引性设计思想，并以此设计了机械手速度观测器，以及基于观测器的机械手输出反馈控制系统，与以往观测方案不同的是，这一观测器可以保证其观测误差与机械手运动轨迹无关。

Drift entrance pupil in laser scanning system is studied in this paper, detailing in rotated octahedron mirror.

在近代激光测试技术中多面体旋转反射扫描测试系统存在入瞳漂移的问题，带来测试误差，然而经典资料中均未作讨论。

The method in this paper is verified through ANSYS, by using the finite element modal analysis. The calculation for the derrick of an oil drilling rig shows that the error is not exceeding 1\%.

通过ANSYS有限元分析对该估算方法进行了验证，并在石油钻机井架底座的有限元模态分析中应用该方法对系统固有频率进行了估计，误差均不超过1\%。

The step motor can receive digital signal directly and has the ability to response outer environment immediately and has no accumulation error, which often is used in driving system. In this driving system, open-loop control system is composed of stepping motor, which can satisfy the demand not only for control precision but also for the target of economic and practicality. On this basis , the analysis of stepping motor in power calculating and style selecting is also given.

由于步进电机能够直接接收数字量，响应速度快而且工作可靠并无累积误差，常用作数字控制系统驱动机构的动力元件，因此，在驱动装置中采用由步进电机构成的开环控制方式，这种方式既能满足控制精度的要求，又能达到经济性、实用化目的，在此基础上，对步进电机的功率计一算及选型问题经行了分析。

It is found out that the different titling directions of moving mirror affect the system error independently, at the same time they can be added. The original phase of the interferogram is changed slowly or rapidly with the optical path difference changed, and the phase error is different too.

在动镜的运动中，左右方向的倾斜和俯仰方向的倾斜对系统的影响彼此具有独立性，又具有叠加性；干涉图中初相位因子随光程差改变缓慢变化或快速变化，对相位误差的影响也不全相同。

According to themathematic model, influences of different optical path parameters on the focus-errorsignal are analyzed, then parameters of the optical system are optimized.

根据所建数学模型，分析了不同的光路参数对聚焦误差信号FES的影响，并优化设计了光学系统的参数。

In regarding roof garden as the discussion of the feasibility of TMD, by controlling the accurate optimum minimal error of passive controlling the algorithm, calculate out the optimum feedback control of the system.

在将屋顶花园作为TMD的可行性的探讨中，用被动控制准最优控制算法的最小误差激励法，计算出了系统的准最优反馈控制力。

By using a switch in proper time, the front and lagging edges of pulse can be cut off, so that the seperated Walsh subcarriers are obtained, they are the orthogonal functions ...

而误差的主要来源是射频通道非线性引起的交叉干扰，但在目前射频通道的一般水平上交叉干扰最大值小于5％，这已满足一般的工程要求。因此SDM作为一个与FDM和TDM相平行的多路复用系统是完全能用于遥测中的。

The total least squares based on singular value decomposition is a method of solving an overdetermined system of linear equations that is appropriate when there are errors in both and .

摘 要：全最小二乘法是一种解决超定线性系统的方法，它基于奇异值分解，适用于当和都存在误差的时候。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。