查询词典 oscillatory

The following exciting results are revealed: 1 When considering the influence of some nonlinear elements such as hard-limit of exciters, the effects of some devices such as Power System Stabilizer and Static Var Compensator which can introduce positive damping in power system, the reasonability of system parameter values in simulation, the SNB surface and HB surface on the boundary of SSSR will turn close to each other and even coalesce together; 2 Under some conditions, coupling between slow exciters and shunt capacitors will bring negative damping in power system dynamics, which increases the possibility of oscillatory instability. So the power system with mass shunt compensators is easily subjected to the oscillatory instability. In recent years, chaotic phenomena of power system have been reported many times. Some simulation studies even found chaos existing inside the power system SSSR. In this dissertation, chaotic phenomena in power systems are thoroughly studied in order to make clear the relation of chaos and SSSR. The following results are derived: 1 Based on Li-Yorke Theorem and their definition on the chaos, the existence of chaos in power system is verified; 2 Three possible routes of causing chaos in power system are found and deeply investigated. They are route of cascading period doubling, route of directly initial energizing and route of torus bifurcation (or quasi-periodicity). The latter two routes are investigated for the first time in power system stability studies; 3 When the stability conditions of chaos are broken, it is found they can lead to voltage collapse, angle divergence, or voltage collapse with angle divergence simultaneously.

针对在电力系统小扰动稳定区域内可能存在混沌吸引域的有关报道，本文深入研究了电力系统混沌现象的出现途径和与系统失稳模式之间的关系：1利用Li-Yorke定理和Li-Yorke的混沌定义，从理论上证明了电力系统混沌现象的存在性；2发现了电力系统中导致混沌出现的三种可能途径：倍周期分岔导致混沌、初始能量直接激发混沌和经由环面分岔导致混沌，并对后两种新发现的途径进行了较为细致的研究；3发现了混沌极限环破裂导致电压崩溃、角度失稳以及电压崩溃和角度失稳同时出现的现象，其中混沌极限环破裂导致系统角度失稳和电压崩溃及角度失稳同时出现的现象均属首次报道；4证明由微分-代数方程描述的系统模型，其小扰动稳定域的边界只包含HB、SNB和SIB三种分岔界面，在SSSR的内部和边界上，均不可能存在会导致混沌的点，从而将混沌现象排除在小扰动稳定域的研究之外，简化了后者的研究工作。

The oscillatory mechanism of the concrete delivery pump is a slider- crank mechanism composed of piston, cylinder block and the oscillatory rod that is linked with the S tube together.

混凝土泵换向系统的动态特性是由和S管连为一体的摆杆、活塞、缸体所组成的曲柄滑块机构和液压传动系统的动态特性共同决定的。

In the second section,we discuss the asymptotic and oscillatory behavior for aclass of first-order mixed neutral differential equations.

在第二节，讨论了一类一阶混合中立型微分方程的渐近性与振动性。

In the literature in China, most of the related work in biochemical engineering are experimental models based on the lab data, which are hard to explain the nonlinear oscillatory phenomena, and most of the work in biomathematics consider the yield functions as constant, linear functions, or some special cases of our general function.

工程界对于连续发酵的非线性振荡方面的研究大多是采用从实验数据归纳出来的经验模型，很难反映过程的本质；生物数学界有关这方面的模型，其中的函数大多数是文的特例。

Ourresults show that only when the s-d mixing is strong enough,can the bilinear orthe biquadratic coupling show an oscillatory behavior in the experimental range ofthe spacer thickness.

我们的结果表明，只有在s-d混合作用足够强的时候双线性和双二次耦合强度才会在实验观测的中间非磁金属夹层厚度的范围内表现为中间夹层厚度的振荡函数。

The purpose of this paper is to prove the existence of non-oscillatory solutions to second-order neutral time-lag differential equation with positive/negative coefficient by using contraction-image principle through defining an operator from a bounded,closed,and convex subset into Banach space.

通过定义有界闭凸子集到B anach空间上的一个算子，应用压缩映像原理讨论了带有正负系数的二阶中立型时滞微分方程非振动解的存在性，得到该方程非振动解存在的一个充分条件。

In the Cathodoluminescence images the zircons extracted from the dioritic gneiss show good crystal morphology and clear oscillatory zoning, as is the case of magmatic zircon.

在阴极发光图像中，片麻岩中的锆石具有较好的晶形，并显示出清晰的岩浆锆石韵律环带结构。

A new method, rotationassembleaverage method, for the oscillatory boundary layer flow around a circular cylinder, was proposed.

提出了一种用于模拟圆柱绕流的振荡边界层流动的新方法——旋转系统平均法。

Numerical simulations of flow structure around a circular cylinder in oscillatory flow, ranging in Kc from 1 to 5 and β from 10 to 1665, are presented in the paper.

并与U型振荡水槽中的流场涡结构显示照片比较，计算结果表明，数值解在稳定性和收敛性方面都是比较好的。

We also show that the conductance in the intermediate regime has an apparent oscillatory behavior.

研究结果还表明，电导在中间能量方式时呈现明显的振荡行为。

The work of this paper is as follows: 1. Looking back the progressing history of the linear motor, introducing the features of the elevator driven by linear induction motor, radicating the topic of this paper "the digital frequency variable control of the elevator bi-side direct driven by linear induction motor". The research of this paper covers the conventional VVVF control, space vector based VVVF control, vector control and DTC.

本文主要开展了以下几个方面的工作： 1 回顾了直线电机发展历史，电机的驱动技术演变，特别是针对直线电机的驱动，简要介绍了直线感应电机驱动电梯的优点和不同结构类型，对传统的v／f控制，基于空间矢量法的v／f控制，矢量控制，和基于电压空间矢量的直接转矩控制进行了比较，确立了本课题的研究主题：直线感应电机双边直推式驱动电梯的全数字变频控制。

The article combines with the treatment of a superficial civil air defense work to introduce how the grouting method to improve the performance of the backfill soil.

文章从治理漂浮人防工事的角度提出了注浆技术在改善回填土性质方面的应用，并详细阐述了注浆技术的施工流程。