小角

Based on varying process of generator terminal parameters after excitation fault, shortages of excitation protective principle of static stability boundary and asynchronous impedance boundary are analyzed. It proposed that excitation fault research relates to large-disturbance stability. Because dynamic power-angle character of generator after excitation fault is non-sinusoidal, there are differences between dynamic power-angle character and static state power-angle character. So it isn't ideal to protective operation result based on small-disturbance stability and static stability boundary criterion. At the same time, it proposed that asynchronous boundary impedance criterion is a constant reactive power circle moving adown j Xd′. It can ensure complete loss-of-excitation generator measuring impedance enter into the circle, but can't ensure the other condition measuring impedance including impossible losing synchronism enter. So loss-of-excitation protection would be maloperation when system voltage drops short and recovers or generator rejects load.③Based on stability principle, it puts forward setting conditions and calculation method of generator loss-of-excitation protection by direct measuring power-angle.

以励磁故障后发电机端的相关参数的变化为基础，通过对以静稳定边界和异步阻抗边界作判据的两类三种现行励磁保护在原理上存在的缺陷分析，发现：励磁故障是一个大干扰稳定性问题，励磁故障后的发电机的动态功角特性与静态功角特性有很大的差异，已远非正弦曲线，因此基于小干扰稳定性原理、以静稳定边界作判据的保护必然动作不理想；异步边界阻抗判据是一个下移j Xd′的等无功阻抗圆，它可以保证完全失磁后的发电机测量阻抗能进入该阻抗圆，但不能保证完全失磁之外的其它状态不会进入该阻抗圆，因此在系统电压短时下降或发电机突然甩负荷等情况下可能启动该保护使之误动。

Experiments using the down-scaled vehicle prove that the static direct yaw moment control significantly reduces the side slip angle at the center of the gravity Also the experiment results indirectly show that the 2 degree of freedom vehicle model is rather accurate.

仿真实验表明集成控制系统可以使汽车在各种运行情况下质心处侧偏角很小的同时，有效跟踪理想横摆角速度响应。模型小车实验也证明静态横摆力矩控制可有效减小质心处的侧偏角，并间接证明二自由度汽车模型准确性。

When the angle radius of the diffraction spot's the first dark ring is big, the effect is relatively small. But when the angle radius is small, especially for turbulent effects being weak, the effect on the beam spreading is very distinct, and the magnitude of the beam spreading is mainly dependent on the jitter item of the scaling relations.

由此定标关系可知，当系统衍射角σ0较大时，跟踪抖动对光束扩展的影响比较小；但是当系统衍射角σ0较小时，特别是在湍流效应较弱的情况下，抖动的影响非常显著，此时光束扩展主要是由系统抖动项所决定的。

In the modal of computing elevation angle and azimuth angle of satellite,we ignore the impact of precession,nutation and pole shift in the process of coordinate system transformation due to their small effects.

在卫星俯仰角和方位角的计算模型中，针对岁差、章动和极移的影响相对于卫星位置是二阶小量，因此在坐标系转换过程中忽略岁差、章动和极移的影响。

the conditions of acquisition of minimum deviation is proved by means of rolle's theorem and the reversibility principle of beam path for triple prism, it is that the angle of incidence is equal to the angle of emergence for monochromatic incident beam.

利用数学中的罗尔中值定理及光路的可逆性原理证明了三棱镜获得最小偏向角的条件，即单色光线的入射角等于出射角。

Experimental transmission of an unnamed bovine Babesia by Hyalomma spp., Haemaphysalis longicornis and Boophilus microplus: Experiments were undertaken to determine the mode of transmission to cattle of an unnamed Babesia sp.

二。采用蜱传播试验，研究了璃眼蜱蜱种、长角血蜱和微小牛蜱对牛的巴贝斯虫未定种的传播能力与传播方式：为了确定小亚璃眼蜱、残缘璃眼蜱、麻点璃眼蜱、长巴贝斯虫未定种的发现及牛巴贝斯虫病的免疫诊断和药物防治研究角血蟀和微小牛蟀对在我国分离的牛的一种未命名的巴贝斯虫的传播能力与传播方式而进行了研究。

I shook to shake head, he says immediately after: What to see did not see me this big is 8 Capes of 4 dollars, he that is small is 4 Capes of 2 dollars.

我摇了摇头，他接着说：看没看见我这个大的是4元8角，他那个小的是2元4角。

And, four kinds of typical reflecting systems were discussed in detail. Comparing the results, it is found that the angular blur spots in a Dall-Kirkham system and an inverse Dall-Kirkham system are at the same order of magnitude, which is almost ten times of a Cassegrain system′s.

详细讨论了四种典型的反射系统，Dall-Kirkham系统和反Dall-Kirkham系统的弥散斑角宽尺寸在一个数量级上，大约为卡塞格林系统的十倍。R-C系统的弥散斑角宽最小，几乎是卡塞格林系统的十分之一。

This article first antenna, microstrip theory, the circular polarization technology, the theoretical discussion, in this based on the microstrip antenna of circular polarization method - corner square microstrip antenna, and has done a design simulation , and then do the design and further research to improve and eventually get a resonant frequency (S11 reflection coefficient corresponding to the minimum frequency) for the 1.5GHz and 1.43GHz, the frequency of circular polarization for the 1.46GHz, S11 is less than -10dB relative bandwidth, the VSWR is less than 2 is about 8.8% relative bandwidth, axial ratio less than 3dB relative bandwidth of about 2.2% of the right circular polarization microstrip antenna design case, which proved very good the circular polarization microstrip antenna theory, also fully confirmed by a square corner design is a practical program, and select the appropriate regulation of sticks is indeed able to improve the performance of the antenna.

本文先对天线、微带理论、圆极化技术等进行了理论论述，在此基础上，提出圆极化微带天线的实现方法——切角方形微带天线，并对此做了设计仿真，后又对这一设计方案做了改进及进一步研究，最终得到一个谐振频率（反射系数S11 的最小值所对应的频率）为1.5GHz和1.43GHz，圆极化频率为1.46GHz，S11 小于-10dB 的相对带宽、驻波比小于2 的相对带宽约为8.8%，轴比小于3dB 的相对带宽约为2.2%的右旋圆极化微带天线的设计案例，从而很好的印证了圆极化微带天线理论，也充分证实了切角方形是一种切实可行的设计方案，而选取合适的调节枝则确能提高天线的性能。

However, because of the limitation by circular orbit, we can't obtain all the data in Radon Space which means that the result becomes better with the cone angle decreases. So it is important to study the relationship between the cone angle and the reconstruct quality further.

但是由于圆轨道几何结构的限制，使其不能够得到完备的锥束重建数据，只有在锥角较小的情况下才能得到，因此深入研究Radon空间的数据缺失与锥角的关系以改进算法。

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。