突然下降

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。

But in the past few weeks, suddenly discovered that the production cost of electrolytic aluminum unknowingly dropped.

但在过去几周里，突然发现，电解铝的生产成本在不知不觉下降。

Remember, once TechCrunch or GigaOm writes about you, you'll most likely get crushed with a single surge of traffic (we fondly call it the "blog spike"), only to watch almost all of it flitter away.

记住，一旦 TechCrunch 或者 GigaOm 写到了你，你很可能会由于在同一时间内突然增加的流量而当机（我们深情地将之称为"博客高峰"），然后看着流量无规律地下降。

The decrease and following return of tension do not work the same way as they have done previously, the music appears to be steering towards another sudden fortissimo but then becomes stuck in repeated, strident discords between brass and piano.

下降和紧张状态的回归与先前不太一样，音乐在看似将又一次出现突然而来的最强音时却开始反复起来，铜管乐队和钢琴演奏着刺耳的不和谐音。

Basically when you suddenly feel panicky or anxious, you put a couple of drops in your mouth and thats it.

基本上当你突然觉得恐慌或焦虑，你把一对夫妇的下降，你的嘴和多数民众赞成它。

However, at present there is a progressive voice to occupy the mainstream: Beijing house prices is neither sudden surge to fly and will not drop.

然而，目前是一个渐进的声音占据主流：北京房价既不是突然飞，也不会下降。

Suddenly in the fog, I saw a red light flashing; then a sort of helicopter was descending towards me.

突然在浓雾中出现一道红色的闪光，紧接着一架类似直升机的物体，正在向着我缓缓下降。

We took a wide sweep into the Bordesley Green Road, and suddenly, when opposite the Directors' mess room, the vehicle heeled to the near side and dropped on its sprag.

我们采取了广泛的扫到bordesley绿道，突然间，当对面的董事餐厅，富有的车辆向附近的方和下降就其

When the internal pressure of liquid, which dropped below the liquid at that temperature the saturation vapor pressure at the local area or the formation of steam bubble point; and stress at elevated places around the bubble suddenly breaking pressure, flow due to inertia to high speed to the center of bubble extrusion, hydraulic shock caused by the equipment.

当液体内部压力下降，低于液体在该温度下的饱和蒸汽压时，在局部区域形成汽泡或汽穴；而在压力升高的地方汽泡突然被四周的压力压破，液流因惯性以极高的速度向汽泡的中心挤压，对设备造成水力冲击。

Just like Friday I desperately struggled to seat my axe in the crux tin-opener 胸带?. I screamed to Joe to expect a fall and released my left axe, cutting loose onto one arm. The axe slid and jerked a centimeter. My heart missed a beat and the jolt nearly made me fall, my hand sliding down the upside-down axe to the head and rolling onto three fingers.

后来爬到 crux时，在爬到后来的他用2.5小时领攀了那段路线，我大声的呼叫 Joe，希望他往下降一点，帮我把挂在左面的冰斧取出来，试图两手轮流砍冰前进，但我好像没有把冰斧固定住，突然滑动了大约一厘米，我一紧张，斧子从手里滑了下来，差点碰到我的头，刹那间我用三个手指头再次抓住它，就在这一瞬间，我整个身体差点坠落下去，心也一下子提到了嗓子眼，砰砰直跳。

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。