查询词典 oscillation

Based on the laser longitudinal mode splitting theory, a novel scheme of dual-frequency laser with large frequency-difference is presented using electrically controlled birefringence of liquid crystal, and the transmitted resonant mode splitting by birefringent of Fabry-Perot etalon has been analyzed theoretically. A new element of liquid crystal Fabry-Perot etalon is designed and fabricated, which serves as aselector and splitter of both laser longitudinal modes and Fabry-Perot etalons transmitted resonant modes. Two different experimental systems of laser-diode end-pumped Nd:YAG laser have been set up using two different LDs, and the transmission of liquid-crystal cell have been measured. When the empty LCFP is inserted in the cavity of high-power LD pumped Nd:YAG laser, the oscillation of a single laser longitudinal mode have been observed, such a result shows that the designed and fabricated LCFP element is capable of selecting single axial mode. While an anti-reflected liquid crystal cell is inserted in the cavity of Nd:YAG laser end-pumped by the high-power LD, it is difficult to confirm weather the laser longitudinal modes have been spitted or not. The subject is summarized in this thesis and the improvement of the project has been presented.

论文以激光纵模的分裂理论为基础，提出了可望获得几十GHz甚至上百GHz的液晶电控双折射双频Nd：YAG激光器的总体方案，并对用双折射效应分裂F-P标准具透射谐振模进行了理论分析；设计并加工了一种集激光纵模选择、激光纵模分裂和F-P标准具谐振透射模分裂于一体的多功能元件——液晶电控双折射F-P标准具；建立了两种不同功率激光二极管端面泵浦的Nd：YAG激光实验系统，并对液晶盒的透射性质进行了测试；将未灌注液晶的空液晶F-P摘要标准具插入大功率LD泵浦Nd：、叭G激光谐振腔内，观察到了单纵模激光输出，说明所设计和加工的液晶F一P标准具具有纵模选择能力；将镀有增透膜的液晶盒插入大功率LD泵浦Nd八7AG激光谐振腔内，是否产生了激光纵模分裂现象还难以确定。

The oscillation of a class of second order strongly sublinear delay differential equations is discussed.

讨论了一类二阶强次线性时滞微分方程解的振动性质，建立了三个新的振动性定理。

After measurement of airway pressure, airway flow, and esophageal pressure, tachypnea was proved to be caused by ventilator autotriggering as a result of cardiogenic oscillation.

在测量了呼吸道压力、食道压力以及气流后，病人呼吸急促的原因证实为心脏震颤造成之呼吸器自发性驱动。

Stability, robustness and oscillation of differenct uncertain time-delay systems are analyzed. Synthetical time-delay control schemes are proposed, including robust stabilizing control, variable structure control, robust dissipative control and so on. Industrial time-delay system model are established based on the theorematic results and industrial requirements. Pratical control algorithms and APC-software are developed and applied to practical process successfully.

在国家自然科学基金资助下，本项目对各类不确定时滞系统的稳定性分析、振动性质分析、鲁棒镇定控制器设计等问题进行了全面的理论分析，并结合流程工业生产过程的特点和企业需求，建立工业过程时滞系统模型，开发实用型的控制算法和先进控制软件，在一些典型的工业生产过程进行了成功的应用，取得了显著的经济效益和社会效益。

According to the definition and the distribution of VSR's voltage space vector, the introduction of a rule-based SVPWM current control strategy, with non-fixed switching frequency and dual hysteresis loops, that obviously improves the performance of current control. Based on two kinds of control strategies of VSR under unbalanced grid condition, the introduction of a new VSR control strategy featuring undamped-oscillation that simplifies the controller structure and effectively improves VSR's performance under unbalanced grid condition. A systematic description of the state switching in trilogic PWM signal generation of threephase CSR by using the conversion between bilogic and trilogic switching functions.

作者在如下工作的基础上对PWM整流器的一些关键问题提出了自己的研究思路、观点和方法：根据PWM整流器网侧矢量关系，直观地描述了其四象限运行的基本原理及特征；定量分析了VSR、CSR的PWM换相过程及波形特征；引入等效变压器模型并详细分析了VSR、CSR基于d—q模型的动、静态特性；提出了满足四象限有功、无功运行指标时的VSR交流侧电感设计方法；并提出了依据控制系统跟随性和抗扰性性能指标设计VSR、CSR直流侧储能元件的参数计算方法；在研究了VSR电流控制策略基础上，提出了影响VSR电流控制的几个要素，并进行了定量分析；根据VSR空间电压矢量的定义及分布，提出了基于规则控制的不定频滞环空间矢量PWM电流控制策略，并由此提出了具有双滞环特性的不定频滞环优化SVPWM电流控制策略，有效地改进了滞环PWM电流控制性能。

Based on two kinds of control strategies of VSR under unbalanced grid condition,the introduction of a new VSR control strategy featuring undamped -oscillation that simplifies the controller structure and effectively improves VSR"s performance under unbalanced grid condition.· A systematic description of the state switching in trilogic PWM signal generation of three-phase CSR by using the conversion between bilogic and trilogic switching functions.· Referenced to the CSR"s trilogic PWM signal generation, an approach to achieve low-stress natural commutation of switching devices by reshuffling the vector composition sequence, resulting reduced switching loss.

在研究了两类电网不平衡时的VSR控制策略基础上，提出了一种新型的基于无阻尼振荡控制器的VSR不平衡控制策略，在简化控制结构的同时，有效地改善了电网不平衡时的VSR控制性能；·通过二、三值逻辑开关函数间的转换，系统地描述了三相CSR三值逻辑PWM信号发生中的状态切换；·结合三相CSR三值逻辑PWM信号发生规律，提出了通过调整矢量合成顺序而使功率管获得自然换相的低电压应力SVPWM控制，从而有效地降低了功率管的开关损耗。

The new variator shifting model can avoid large shifting range and shifting rate oscillation.

新模型克服了以往模型在速比变化过程中，速比变化率响应范围过大、速比变化率振荡的不足。

According to the ac cident survey and the field test data,the paper analyses the reason of tower body discharge due to jumping wir e, solves the problem fundamental way to reduce wind oscillation of jump l ine insulator string and the relaxation degree of jump line.

根据事故概况及现场测试数据，通过计算就跳线对塔身放电原因进行了认真分析认为解决引流跳线对塔身放电最根本的措施是要减小跳线绝缘子串的风偏摆动和减小跳线的松驰度。

In every theta cycle this type of interneuron fired in burst with 3-10 spikes. Their firings incline to the positive peak of theta oscillation.

在每个theta循环周期，这类神经元均呈簇状放电，每一簇大约有3-10个电冲动，且放电的最大概率趋向于在theta节律的波峰放电。

The conclusion can provide reference to research into the causes of power system low frequency oscillation.

该研究结果对探讨电力系统低频振荡的产生原因具有一定的参考价值。

I will endeavour to find you some assistance.

我尽力帮你找人帮忙。

At first I only know bruck is the idol of American younglings, afterwards I returned back to Taiwan ,even in Beijing last year ,I saw her poster everywhere, I was so surprised at her charm.

起初我只晓得布鲁克雷德丝是美国少男少女崇拜的偶像，后来回台湾，甚至去年在北京，居然也四处看见她的海报，才惊讶她的魅力之大。