查询词典 periodic

A new method to decide GPS satellite position using the broadcast ephemeris is presented, the way to checkup the precision is also given, and some research are made to analysis the error feature of the position which is calculated hy the broadcast ephemeris as well, the results show the error is periodic.

GPS卫星高度角、方位角计算方法众多，但精度低；针对这点，提出了一种利用广播星历计算卫星高度角、方位角的方法，对该方法能够达到的精度提出了鉴定的途径，并分析了利用广播星历计算卫星高度角以及方位角的误差特点，结果表明利用广播星历计算的卫星高度角、方位角呈现出周期性变化的规律。

In order to reduce the periodic current tracking error of the deadbeat control when compensating abruptly changing nonlinear load current, a repetitive controller is plugged into the deadbeat controller. Also, the repetitive controller can alleviate the parametric dependency of the deadbeat control and eliminate the effects on compensation performance caused by the uncertainties in the system.

另外，为了降低无差拍控制对系统参数的依赖型和系统中存在的不确定性对补偿性能的影响以及减小在补偿电流变化剧烈的非线性负载电流过程中存在的周期性的局部跟踪误差，本文在无差拍控制器的基础上，又提出了基于无差拍和重复控制的复合电流控制器。

The new method is given to design the optimum profile modification curve design The effects of optimum profile gear in improving the dynamic performance of gear transmission are verified in the Gear Dynamic Performance Test Rig In this dissertation, the main study contents and creative results are shown as following: The influences on the gear transmission system caused by the gear's accumulated error (periodic error and harmonic error) are theoretically studied. A new method is developed to simulate the gear's harmonic error by using the 2-order MARKOV process A simulated model of the dynamic performance which is excited by the gear's accumulated error is obtained.

本文在前人大量研究的基础上，结合作者承担的国家自然科学基金项目"齿轮传动动态系统辨识与三维修形研究"和山东省自然科学基金项目"齿轮传动动态性能仿真及结构参数、齿形的优化修形"，采用理论和试验相结合的新思路，系统地研究了齿轮传动的动态性能，建立了能正确描述齿轮传动系统动态性能的仿真模型和系统辨识模型，给出了确定齿轮传动轮齿修形曲线的优化设计方法，利用自行研制的齿轮传动动态性能试验装置，验证了优化修形齿轮对提高齿轮传动动态性能的突出作用。

A measuring system which mainly consists of a high precision motorized translation stage of one dimension, POINT GREY Flea2-14S3 CCD camera and LED light source was designed and constructed. Based on a detailed analysis for experiment results, the periodic changing law of system error of LED facula centroid location in this measuring system was found. The results indicate that based on Flea2-14S3 CCD camera, the random error of facula centroid location is about 0.018 pixels, the system error is about 0.06 pixels, and the total error is about 0.063 pixels (1/15 pixels).

利用高精度一维电动平移台、POINT GREY Flea2-14S3 CCD 相机和LED 光源构建了测试系统，对测试结果进行研究和讨论，发现了测试系统LED 光斑质心定位系统误差的周期性变化规律，计算得到了基于Flea2-14S3 CCD 相机的光斑质心定位随机误差为0.018 pixels，系统误差为0.06 pixels，总体误差为0.063 pixels(约1/15 pixels)，能够应用于以光斑质心检测为手段的测量系统中。

By measuring missile movement inertia with torsion pendulum, the influences of periodic measurement error, systemic damp, period of swing object and corporative period of t he measured object and swinging object were analyzed. The relation among measurement error of movement inertia, measureme nt period, the period of swing object,corporaˉ tive period of tested object and swing object was proved. The maxi mal ratio between movement inertia for swinging obˉ ject and the measured object under conditions of different errors w as given under typical measurement precision.

通过扭摆测量导弹转动惯量的方法，分析了周期测量误差、系统阻尼、摆动体周期以及被测件和摆动体共摆周期对转动惯量测量精度的影响，得出转动惯量测量误差和周期测量误差、摆动体摆动周期、被测件和摆动体共摆周期之间的关系，给出了在典型的测量精度要求，不同的周期测量误差情况下，摆动体转动惯量和被测件转动惯量之间的最大比值。

A measuring system which mainly consists of a high precision motorized translation stage of one dimension, POINT GREY Flea2-14S3 CCD camera and LED light source was designed and constructed. Based on a detailed analysis for experiment results, the periodic changing law of system error of LED facula centroid location in this measuring system was found. The results indicate that based on Flea2-l4S3 CCD camera, the random error of facula centroid location is about 0.018 pixels, the system error is about 0.06 pixels, and the total error is about 0.063 pixels (1/15 pixels). According to the total error above, this CCD imager can be widely used in many measuring systems which count on facula centroid subpixel detection.

利用高精度一维电动平移台、POINT GREY Flea2-14S3 CCD相机和LED光源构建了测试系统，对测试结果进行研究和讨论，发现了测试系统LED光斑质心定位系统误差的周期性变化规律，计算得到了基于Flea2-14S3 CCD相机的光斑质心定位随机误差为0.018pixels，系统误差为0.06pixels，总体误差为0.063pixels（约1/15pixels），能够应用于以光斑质心检测为手段的测量系统中。

The performance of BCH(63,39,4) and BCH(127,78,7) code using these two schemes and periodic interleaving scheme in mobile fading channels is obtained by simulation.

并对采取这两种交织方案的BCH(63，39，4)，BCH(127，78，7)码在移动衰落信道下的纠错性能进行了计算机仿真，且与周期交织方案的结果作了比较。

Using characters of periodic fading of channel in frequency selectivity, the invented method partitions orthogonal FDM modulation sub carrier wave into some sub bands in two types crossed arranged to be assigned to two typed users.

一种正交频分复用调制子载波分割与子带交叉排列的方法，用于数字信息传输技术领域。

This paper explores the two important properties of periodic function by an example.

文章用一个反例指出了周期函数的两个重要性质的缺陷。

Firstly it defines a periodic moment function based on the region of a shape.

该算法是一种基于区域的不规则形状描述法。

By the time of its fall, most of the prisoners were writers who had written against the corruptions of the government.

到它被攻陷的时候，里面多数的犯人是写了反对政府贪污文章的作家。

The most obvious variation to ovum morphological character was that the color was changed from light green to sepiaceous in embryonic development, and all the ovums were almost hatched after 96h.

在胚胎发育过程中卵的形态特征最明显的变化是颜色从淡绿到深褐色，卵在发育96h后卵基本全部孵化。