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In this paper, a novel Crowbar control strategy is proposed to limit the over current in the rotor and the over voltage of the DC bus as well as the transient oscillation of the electromagnetic torque. Moreover, a capacitive current is injected into the grid to assist the recovery of the grid voltage.

文章提出了一种Crowbar控制策略，能有效抑制转子过电流、直流母线过电压以及电磁转矩的振荡，并可向电网注入无功电流以帮助电网电压的恢复。

Due to its good effect in the reservation of information of signal abrupt change, mathematical morphology is often applied in the detection and location of short-term power quality disturbance, however, there is still a defect of invalid detection existing in partial detection methods based on mathematical morphology while some zero-crossing disturbances are detected. In this paper three mathematical morphology based disturbance detection and location methods, i.e., the method based on first-order derivation and morphological gradient, the method based on morphological gradient and soft threshold processing and the method based on dq decomposition and top-hat transform, are analyzed, that is, by means of simulation the adaptability of these methods in the analysis on the signals of voltage sag, voltage swell and electromagnetic transient oscillation is compared.

数学形态学因其在保留信号突变点信息方面有很好的效果，因此常用于短时电能质量扰动的检测和定位，但基于数学形态学的部分方法仍存在对某些过零点扰动检测失效的缺点，文章分析了3种基于数学形态学的扰动检测和定位方法，即基于1阶求导和形态梯度的方法、基于形态梯度和软阈值处理的方法、基于dq分解和高帽变换的方法，通过仿真比较了3种方法在分析电压暂降、电压暂升、电磁暂态振荡等信号方面的适应性，结果发现基于dq分解和高帽变换的方法在检测过零点扰动时具有很好的效果，因此选取这种方法对实测扰动数据进行了检测和定位分析。

ABSTRACT Some new advances in transient electromagnetics are introduced in this dissertation, which presents further insight into the ener...

本论文介绍了我们在非正弦电磁波的辐射与传播研究中取得的一些新进展。

For the first time, we investigate the ultrafast process of electron excitation, structural transition and ablation in ZnO films by using transient reflectivity measurements.

在实验上，我们用瞬态反射率测量技术首次研究了ZnO薄膜的电子激发、材料结构相变以及烧蚀的瞬态过程。

Finite element analysis of laser-induced transient surface grating fields of diamond/ZnSe.

金刚石/ZnSe结构中瞬态热栅场的有限元法分析。

Within this context, four specific areas are addressed:(1) By means of finite integration technique, a new kind of the first order partial difference equation is derived from the original disperse transmission line equation of the uniform waveguide's. As it is the kind of one dimension Dirichlet's boundary problem, it is convenient for us to solve this equation from the leapfrog scheme. Because computation is carried out in one dimension, both high calculation efficiency and precision have been obtained in this method. Meanwhile, this method provide us a different selection to simulate the transient response of waveguide with non-simplical, for examples cylinder and elliptic waveguide, and avoid solving the second order equation, or using finite difference time domain to simulate a three dimension problem, sometimes the latter precision is not satisfied with the need, or low efficiency.

在这一研究内容下，主要研究四个方面的问题：(1)在完成金属波导传输线方程时域形式的基础之上，应用有限积分技术，把波导特征模式的色散传输线方程，化简为一组新的一阶偏微分方程组，该边值问题属一维Dirichlet边值问题，从而便于用蛙跳格式求解，由于是在一维中计算，该方法具有很高计算效率和精度，从而避免了以往为得到金属波导中特征模的时域响应特性，须要求解二阶方程，或用时域有限差分方法求解三维问题的方法，对于后者来说，计算有时是不准确的，或是很耗时的例如计算诸如圆波导、椭圆波导等其它复杂形状的波导。

However,highly selectiveκagonists produced transient sedation and emesis,although tolerance developed to these effects during chronic treatment.

许多证据表明传统高选择性κ-受体激动剂不仅具有较高的镇痛作用，而且还克服了与μ受体相关的副作用，尤其是能够抑制阿片类物质成瘾。

The purpose of this study was to describe the clinical features and encephalography findings in 7 infants treated in our center for a syndrome of transient encephalopathy associated with adenoirus infection.

本研究的目的在于探讨我们中心7患儿的临床特征和脑电图发现与腺病毒感染的关系。

Based on the above results, the new transient stability analysis method of normalized energy function is proposed.

基于上述理论分析，提出了构造电力系统归一化暂态能量函数的方法。

The main idea of this dissertation is as following sequence: disturbance signal denoising, transient harmonic measurement, disturbance online detection, and PQD data classification mining. Utilizing wavelet theory, Teager energy operator, and data mining technology, this dissertation presents a comprehensive and systematic study of PQD online detection and classification.

本文针对这两个核心问题，沿着"扰动信号去噪暂态谐波测量扰动在线检测扰动数据分类挖掘"这一技术主线，运用小波理论、Teager能量算子和数据挖掘技术，对电能质量扰动信号去噪、暂态谐波测量、扰动在线检测以及扰动数据分类挖掘进行了系统研究。

Cable dampener cannot be rolled up but must be hung over the cable.

缆帆不能被卷起，必须保证处于展开状态

"This skylark is a present from my master," he says.

"这只云雀是我主人献上的礼物。"他说。