查询词典 by error

a scheme of channel estimation using cyclic prefix based on the measurement of the low-voltage power line channel model is presented.after obtaining the frequency response of pilot sub-channel under the state of comb-type pilot,the data sub-channel response is obtained by interpolating the frequency response in frequency direction.in the pilot-free data period,the estimation of the channel is carried out by using cyclic prefix in order to improve the performance of system error rate.

摘 要：通过实际测量给出低压电力线的信道模型，在此基础之上提出了利用循环前缀对信道进行估计的方法，即在梳状导频模式时，使用导频获得导频子信道频率响应后，对其在频域方向进行插值得到数据子信道响应，在其后没有导频的序列的数据周期内，使用循环前缀对信道进行估计，从而起到改善系统误比特性能的目的。

Cyclic Redundancy check code is recommended by International Telecommunications Organization , used in the digital communication system error control coding way (given several coding generator polynomial), they have been widely used by the people in the digital communication system.

循环冗余检错编码是国际通信组织推荐的用于数字通信系统的差错控制编码方式（给出了几种编码的生成多项式），已被人们在数字通信系统中广泛地使用。

Objective To compare the reflective error by retinoscopy with that by autoretractian in cycloplegic children's eyes.

视网膜检影法是一种利用检影镜来检查被检眼静态屈光的客观检查方法。它简单、常用。

A new calculation model is established using the simulating curves presented by Standing and Katz. The coefficients of the correlation are determined by fitting to the data of Standing and Katz Z-factor chart. The results of the two models are compared, the conclusion can be drawn that the error of LXF model is smaller than that of DAK model.

利用两种模型对不同拟对比温度和拟对比压力组合条件下的天然气偏差系数进行了拟合计算，与理论图版值的误差对比显示，在高温高压条件下LXF模型的拟合结果更优，特别是随着拟对比压力的增加，LXF模型的误差不断减小，因此，该模型更适用于高压和超高压条件下天然气偏差系数的工程计算。

As for the measurement of satellite baselines, only an order of decimeter precision can be obtained just by instruments. Fortunately, the error can be estimated and corrected by signal processing.

对于编队卫星基线的测量，仅仅利用测量仪器通常只能达到分米级的测量精度，可以利用信号处理的方法进一步估计并校正阵列误差。

Marsh 190, was decided by the Kentucky court of appeals in 1820. It was there urged that the testator intended to have destroyed his will, and that he was forcibly prevented from doing so by the defendant in error or devisee; and it was insisted that the will, though not expressly, was thereby virtually, revoked.

一个案件是1820年肯塔基州上诉法院判决的盖恩斯诉盖恩斯案，该案说遗嘱人试图撕毁所立遗嘱，但被告或受赠人恶意阻止其撕毁遗嘱，遗嘱最终得到支持，没有被撤销。

For the diffractive optical element realizing beam shaping in the fractional Fourier transform domain,the transform matrix calculated by the discrete sampling points was compared with that calculated by the Fresnel integral,and the discretization error of the intensity distribution on the output plane was qualitatively obtained.

针对分数傅里叶变换衍射光学光束整形器件，比较了按离散点与按菲涅耳积分计算得到的变换矩阵间的差距，从中分析得出按离散点计算的变换矩阵引入的离散化误差与分数傅里叶变换系统参数的关系。

The Periscope Drawtube will be bent because of the water resistance in sailing and this bend will cause the error of star measurement. Due to its especial structure, contactless measurement is the only way to measure its bend degree. First this paper introduces the method by linear array CCD based on structure and light path; Second it expatiates linear array CCD work principle and driving scheduling with example of TCD1501C and the driving circuit by CPLD. The output signal of linear array CCD includes common disturbance so the differential amplifier is needed. In order to make the signal adapt to computer processing, a threshold circuit with Schmitt characteristic and the data process following threshold are given. At last, some key problems in application are given.

潜艇潜望镜的镜筒在航行时受到水的阻力会产生弯曲变形，这种变形会造成潜艇对星体测量的误差；由于镜筒结构的特殊性，对其弯曲程度的测量只能采用非接触方法；首先从结构和光路方面介绍采用线阵CCD作为检测元件实现对镜筒弯曲程度的测量；其次以东芝公司的线阵CCD（TCD1501C）为例阐述了其工作原理及驱动时序的控制要点，并介绍了基于可编程逻辑器件的线阵CCD的驱动电路；线阵CCD输出的信号中含有共模干扰，必须采用差分放大器将其抑制；为将信号转化为适合计算机处理的数字信号，文中给出了有一定实用价值具有施密特特性的二值化处理电路及二值化后的数据处理过程；最后阐述了在实际使用中的一些关键问题。

Conventional meteorologic radar cannot distinguish radar reflectivity and specific attenuation of rain. There is some principled error to measuring rain by it. A new method on inversing rain rate distribution along Earth-Space path by radar-satellite system is presented in this paper.

一种改进气象雷达测雨性能的新方法胡大璋（中国电波传播研究所青岛研究中心，青岛266003）常规气象雷达无法分离雷达反射率和雨衰减率，因此用它测雨具有一些原理上的误差。

The main problems researched in the dissertation and achievements are as follows: The dissertation explains the science background and the theoretical and actual meaning of the task. The progress and the problems of the flow imaging technique are briefly explained. The advantages of electrical capacitance tomography are discussed. The paper discusses the formation and operating principle of ECT, and builds up the definite mathematical model by detail theoretical analyse, and establishes the Finite Element Model of the system by changing the finite boundary value problem of ECT into equivalence variation problem according to variation principle. On the basis of the FEM of the system, the paper builds the finite element model of the capacitance sensitivity field distribution and programs its finite element simulation software and proves the validity of the FEM of the ECT from different aspects. With the FEM and the qualitative analyse of the effect of each structural parameter of the capacitance transducer on its capability, this paper optimizes the structural parameters of the capacitance transducer, and obviously improves its capability. The compare of the simulated result with the static experimental result shows that the error of them is less than 0.9%.

其主要研究内容包括：阐述课题研究的学术背景及其理论与实际意义，概括总结出流动层析成像技术的发展现状和存在的问题，指出电容层析成像技术的优点；讨论电容层析成像系统的组成及工作原理，进行详尽的理论分析，以变分原理为基础，将ECT的有限元边值问题转换为等价的变分问题，从而建立系统的有限元模型；在系统有限元模型的基础上，建立敏感场的数学模型，编制有限元的仿真软件，并从不同角度证明电容层析成像系统有限元模型的正确性；利用有限元模型，定性地分析电容传感器各结构参数对其性能的影响，并对传感器结构参数进行优化设计，使其性能得到明显的改善。8电极ECT系统的仿真和静态实验结果的比较表明，它们之间的相对误差小于0。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。