差

By using the Tadmor's convergence criteria for the difference approximation of the hyperbolic conservative e2 quation and introducing some adjusting parameter in the nonvanishing viscosity , some convergence properties are obtained.

Descripción ：摘要：应用Tadmor 的关于双曲型守恒方程式差分逼近的收敛性判别法，对于若干差分逼近式，引入一些参数，只要在上机时适当调整此参数值，即可得到其收敛性。

Direct difference is sensitive to noisy data, so a threshold limitation is given, which can not only filter the result from noisy data but also pick edge points up according men's desire. On the other hand, artificial intelligence is used for segmentation in reverse engineering. Because the essence of segmentation is clustering similar characteristics and self-organizing feature mapping is one function of neural network, SOFM network is used for segmentation in the thesis, coordinates and normal of data points is took as the characteristics vector.

第二种方法，基于双向角度微分的边点提取法，针对三维正交模型采用基于截面线的方式组织数据，此方法比基于曲率半径方法更简洁，不用进行曲面拟合，大大提高了计算速度；计算过程中由数据点的直接差分逼近微分，但直接差分对数据误差敏感，为此，本文提出了阈值过滤的方法，一方面过滤了数据误差在计算结果中引起的噪音，另一方面可以按照设计意图控制边点的提取；来决定是否提取光滑交接的边点。

In this paper, the stability of the normal equations in the adjustment and its effects on the estimation of parameters are discussed in a great detail along with the methods and theories of GPS short—arc adjustment.

本文分析了在GPS定位中平差模、型法方程组系数矩阵状态的稳定性及对参数估计的影响，进一步探讨了适合于GPS短弧法平差的理论和方法。

Based on the third-order aberration theory of two-mirror reflecting system, the influence of the geometrical aberrations on the performance of normal incidence telescopes was analyzed.

基于三级象差理论，分析了几何象差对正入射望远镜性能的影响，总结了弥散斑角宽度θ随着系统f数和半视场角uP的变化趋势。

A simple of improving the differential frequency by D flip-flop is introduced. The method is verified by timing analysis. Numberical application conditions are given out. The reason for the error production is analyzed and the maximum error range are calculated.

介绍了D触发器差频的方法和应用条件，用最基础的时序分析的方法，对D触发器差频做一个理论上的验证，定量给出应用条件，并分析了产生误差的原因和最大的误差范围。

In this article,origins of numerator relationship has been proved and the correlative calculation formula deduced .

本文对亲缘协方差的来源及相关公式进行了系统推导，并概括了应用亲缘协方差公式计算动物亲缘系数及近交系数的规则。

Analysis of slewing errors angle is proceeded with measurement error of the drive chain and every effect of errors factor on slewing error is quantitatively analyzed in the paper. And the numeric moel of caculating slewing error angle is established.

本文主要从传动链尺寸误差入手定量分析各项误差因素对FA传动回差的影响，并建立计算回差的数学模型。

The possible differential rotation among the layers of the Earth interior and its contribution to nutation, as well as the displacement profile interior, are studied, which provides a new method to study the differential rotation of the Earth cores.

讨论了地球内部可能的较差转动对章动的贡献以及地球内部形变场剖面，特别是核幔边界附近的低阶形变场的非线性特性，为研究较差转动提供了除地震学之外的另一种新的可能途径。

On the CTP recommendations for the CTP the present status and future development, in my view:(1) the current CTP, yield in China mainland increased year by year, but account for offset plate resulted in a smaller proportion of; in market better brand, with foreign investment and joint venture brand.

二、差CTP的建言差于CTP不幼远的不隐状和畴昔的成不幼，我觉得：（1）不幼远我不国边不天CTP版产量逐年加不幼，但撤离胶印版材总产量的比例仍较小；在阛阓上采购较好的品牌洋，仍以边资、合股的品牌为主。

Results In olecranon plate group,20 cases were excellent,7 cases were good, 1 case was passable and no case was bad;In tension band group,23 cases were excellent,10 cases were good,2 cases were passable and no case was bad.

结果 尺骨鹰嘴钢板组：优20例，良7例，可1例，差0例；张力带组：优23例，良10例，可2例，差0例，两种治疗方法疗效无统计学差异。

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。