振荡的

According to the change of the enemy\'s quantity and the qualitative theory of the differential equation, we research the spruce aphides and its predator system. At the same time, we discussion the spruce aphid multiplication model when the natural enemy quantity is a certain value and the periodic oscillating model whose the quantity of the natural enemy changes along with the time. Obtains the stability condition of the balance point and the limit-cycle existing condition, the system presents the dissipative structure\'s character. Finally it explains that this theoretical analysis has certain practical significance regarding the preventing and controlling harmful insect.

第五章，松毛虫与其天敌的关系是食饵和捕食者的关系，根据天敌数量的变化，利用微分方程定性理论，研究松毛虫与天敌系统，讨论天敌数量为一定时的松毛虫增殖模型和天敌数量随时间变化的周期振荡模型，得到正平衡点全局稳定性和极限环的存在条件，通过计算机模拟，说明周期振荡的捕食模型能够呈现典型的时间耗散结构特征，对于防治害虫有一定的实际意义。

It is:(1)designed according to attenuate vib-ration system of second order.

其特点是按具有衰减振荡的二阶系统进行设计；

Electrical oscillation in the sending coil, which is comprised of a metallic conductor, causes radiation of inductive photons from the sending coil.

电气振荡的发送线圈，这是组成一个金属导体，造成辐射感应光子从发送线圈。

Those with detailed generator models and exciter models. Thus, this proposed method has two

型并利用QR 算法计算出系统低频振荡的结构性特征，第二步发电机采用详细模

In order to improve the reliability of the nuclear Generating Sets and the stabilization of the power system, prevent the long time low frequency oscillation caused by the disturbed of the outside electrical net, assured improving the stabilization margin of the nuclear generating sets in the precondition of enough transient stability, validate the sensitivity of the parameter to the damping of Generating Sets of the MEC5220 digital excitation adjustor produce in Japan that used in the Second Project of Qinshan Nuclear Power Plant, confirm the parameter rationality of the digital excitation adjustor, optimize the parameter of PSS, in this paper, we put up a in-depth study to the principle of MEC5220 digital adjustor produce in Japan by the PSS/E software that develop by the PTI Company in the USA, completed the modeling of the excitation adjustor, PSS, generator, excitor, described the performance of this excitation adjustor, analyzed the essential reason that caused the low frequency oscillation, illuminated the factor that influence the damping characteristic of the MEC5220 digital excitation adjustor. Based on model and emulate, this paper optimized the primary parameter of the excitation adjustor, make a reasonable regulation to the PSS parameter.

为提高核电机组的运行可靠性和接入系统的安全稳定性，防止在外电网的干扰下核电机组发生长时间的低频振荡，保证机组在暂态稳定的前提下提高其稳定裕度，验证秦山核电二期核电机组所配日产MEC5220型数字式励磁调节器参数对机组阻尼的灵敏性，确定数字式励磁调节器的参数的合理性，优化PSS整定参数，本文利用美国PTI公司研发的PSS／E软件对日产MEC5220型数字调节器的原理进行进行了深入细化的研究，完成了励磁调节器、PSS、发电机、励磁机的建模，描述了该型励磁调节器的性能，分析了产生低频振荡的根本原因，阐明了影响阻尼特性的因素。

This phenomenon is called the free oscillation of the Earth.

这种现象被称为自由振荡的地球。

The hydrodynamics of pulsed fluidized beds was studied with four kinds of particles of ...

本文对引入气流强制振荡的脉冲流化床进行了实验研究。

A method for extracting the beta-function and phase of the beam position monitors and the corrector magnets from the measured response matrix based on storage ring theoretical model is presented.

根据电子储存环理论模型，采用迭代方法从实测响应矩阵计算束流横向振荡的振幅函数和相位。

This paper analyses the indicator diagram filtered by traditional GFSF method, shows the advantages and disadvantages of it and provides a modificatory method.

本文分析了传统广义频率抽样滤波法处理示功图振荡的优缺点，并对其进行了修正。

It was found that in the DC bias electric field, when the relaxation time of the hot-electrons in the electron-electron and electron-phonon interaction process is longer than the carrier life, the photoconductivity oscillation can be caused by the change of mobility in the process of optoelectronic transport, which is the main cause for the output electrical pulse to show oscillations.

分析了开关体内载流子的微观状态和输运过程，在直流偏置电场作用下，开关体内的热电子在电子-电子、电子-声子相互作用过程中，当它们的弛豫时间大于载流子的寿命时，光电子的输运可通过迁移率变化引起光电导振荡，这是开关输出电脉冲出现振荡的原因。

And Pharaoh spoke to Joseph, saying, Your father and your brothers have come to you.

47：5 法老对约瑟说，你父亲和你弟兄们到你这里来了。

Additionally, the approximate flattening of surface strip using lines linking midpoints on perpendicular lines between geodesic curves and the unconditional extreme value method are discussed.

提出了用测地线方程、曲面上两点间短程线来计算膜结构曲面测地线的方法，同时，采用测地线间垂线的中点连线和用无约束极值法进行空间条状曲面近似展开的分析。