精度

As a result of case study in Haidian district, Beijing, the accuracy rate of vegetation fraction estimation by using "dense vegetation model" and "nondense vegetation model" synchronously based on land cove classification is obtained about 75.4%, which is 5.8% higher than that of using "dense vegetation model" only.

根据TM像元为非均一混合像元的特点，提出了基于土地覆盖分类的综合运用"等密度模型"和"非密度模型"计算植被覆盖率的方法，通过对北京市海淀市区的植被覆盖率计算表明，该方法的估算精度可达75.4%，比单纯使用等密度亚像元模型在估算精度上可提高5.8%。

Moreover, one set of normal equations is computed from a 7-day orbit arc.

最后累加每7天一弧段之法方程式，计算平均地球重力场模型，发现大地起伏精度在空间解析度1000公里时为5 mm，精度比EIGEN-1S及EGM96佳。

This paper illustrated how to distinguish initial numberical date s precision by means of combination method and error method,which can find out initial numerical dates lower precision point and adjust rupidly.

本文在多年工作实践中分析出产生这种情况的几个原因，提出了用组合法与尝试法对起算数据精度进行判别的方法，能较快地发现起算数据相对精度较低的点，快速进行 GPS网平差。

The author successfully applies the Gauss-type integral formula to the numerical solution to the constant differential equation and creates the Gauss-type implicit Runge-Kutta Method of which the accuracy of order 4 and degree 7 is already equivalent to that of the RK method with order 10 and degree 8 that is in common use.

成功地将高斯型求积公式用于常微分方程的数值解中，得到了高斯型隐式龙格库塔方法，4级7阶 GRK 法的精度已与目前较为常用的10级8阶 RK 法的精度相当。

To high-precision ring permanent magnet torque motor servo system used in direct drive numerical control rotary table with the request of smooth operation at low speed, the precision is mainly restricted by cogging torque.

中文摘要：对于要求在低速下能够平稳运行的高精度直接驱动数控转台用环形永磁力矩电机伺服系统，它的定位精度主要受到以齿槽转矩为主的扰动力矩的影响。

Arithmetic Analysis of Geocentric Vector Based on Earth Sensor for Spheral Model and Oblate Model;2. The accuracy of the measurements of the geocentric vector plays a key role in satellite navigation,but it is affected by the earth oblateness.

卫星利用紫外敏感器和星敏感器进行自主导航的方法中地心矢量的测量精度是影响导航精度的重要因素之一，而地心矢量的测量又受到地球扁率的影响。

France octans marine high-precision navigation system description, can realize the dynamic initial alignment, a high precision.

详细说明：法国octans船用高精度惯导系统的说明书，可实现动态初始对准，精度很高。

Three different numerical iterative algorithms are developed and the accuracy and stabilities of them are compared. Tension and compression instabilities are studied and effects of Conservative Smoothing Approach and artificial viscosity on stabilities are discussed. Based on Taylor series expansion, Modified SPH method is proposed. The discrete forms of the function and its first derivative estimations of the kernel function are deduced in both one and two dimensional space.

讨论了三种不同的数值迭代算法对计算精度和稳定性的影响；分析了不稳定性产生的根源，包括拉伸不稳定和压缩不稳定，探讨了保守光滑算法和人为粘性对稳定性的影响；在Taylor展开的基础上提出了一种修正的SPH方法，并推导一维和二维情形下函数的核估计和函数的一阶导数核估计的离散形式，结果表明，二维情形下MSPH方法可以很好的改善边界粒子的计算精度。

In this paper,we analyze the key techniques for the service precision of Global Navigation Satellite System such as time reference,time synchronization,satellite orbit determination,etc.

对影响导航定位系统定位精度的各种因素进行了分析。研究了影响导航定位精度的关键技术问题，如时间基准、时间同步和卫星定轨等。

In the course of determination orbit, the on-board GPS surveying plays a crucial role, that is the quality of the on-board GPS data.

其中对轨道精度起决定性作用的就是星载GPS测量的精度，也就是星载GPS数据的质量。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。