分岔

ABSTRACT Bifurcations, structural stability and voltage stability for power systems have been investigated in this thesis.

本文主要研究电力系统的分岔、结构稳定性和电压稳定性问题。

In this paper, the bifurcation of 1/2 subharmonic resonance of thin elastic plate in noninertia system was presented.

本文研究了非惯性参考系中弹性薄板在大范围运动与变形运动相互耦合时的1/2亚谐共振分岔。

The critical bifurcation parameter intervals of superharmonic periodic impact motions are deduced, and numerical simulations are used to verify the results.

本论文讨论了碰撞振动系统的周期碰撞运动，得到了超谐周期碰撞运动的存在性和稳定性，推导出亚谐周期运动的临界分岔参数区间，并利用数值模拟进行验证。

In this dissertation, periodic impact motions in vibro-impact systems are studied, and the existence and stability of superharmonic periodic impact motions are obtained. The critical bifurcation parameter intervals of superharmonic periodic impact motions are deduced, and numerical simulations are used to verify the results.

中文题名碰振或约束系统的全局分析及稳定性研究副题名外文题名 Studies on global analysis and stability in vibro-impact or constraint systems 论文作者张彦梅导师陆启韶教授学科专业一般力学与力学基础研究领域\研究方向学位级别博士学位授予单位北京航空航天大学学位授予日期2002 论文页码总数95页关键词碰振系统转子系统多体系统碰撞振动馆藏号BSLW /2003 /O322 /1 本论文讨论了碰撞振动系统的周期碰撞运动，得到了超谐周期碰撞运动的存在性和稳定性，推导出亚谐周期运动的临界分岔参数区间，并利用数值模拟进行验证。

Firstly, the average equation under first,and second order of Van der pol-Mathieu-Duffing system are obtained through theatric methods. According to the stability criteria, the physical parameter plane is divided into different regions, associated with different types of steady state solutions, which are proved by employing numerical methods.

本文首先通过理论分析得到了Van der pol-Mathieu-Duffing方程在一、二阶近似下的定常解，分析了平均方程在不同参数平面内的幅值响应曲线，根据解的稳定性判据得到了物理参数平面上的分岔集以及定常运动在相应平面的分布情况，详细分析了该系统在各个区域内的动力学特性。

Based on the idea of the nonlinear dynamics,especially the Thoms Morphogenesis,a knowledge model,called attracting-bifurcating net,is advanced to solve the problem of knowledge representation and acquisition for visual learning in this paper.

本文基于非线性动力学，特别是托姆的形态发生学思想，针对视觉学习，给出了一种吸引分岔知识网模型，用于解决知识表示和获取问题。

Secondly,as an application ofφ-mapping topological current the-ory,the vortices in TDGL model have been studied.Some importantartificial hyperthesises in other theories have been changed into naturalresults ofφ-mapping topological current theory.The inner structureof vortices system in the TDGL model has been obtained in terms oforder parameter field.For the first time,the branch process of thevortex system in the TDGL model have been discussed.

其次，作为Ф-映射拓扑流理论的重要应用，本文研究了TDGL模型的vortex动力学，对过去该模型中的一些人为假设给予了合理而严格的理论基础，用序参数的Hopf指数和Srouwer度表征了拓扑荷，建立了该系统拓扑性质的新理论，并首次探讨了TDGL模型中的vortex的分岔过程。

Due to the electro-mechanical coupling, the subsynchronous oscillation occurs in the system,which causes the oscillation of electric current, electric voltage and the torsional oscillation of the set of axes.

网机系统机电耦联失稳振荡的分岔与混沌研究项目，共发表学术论文30篇（期刊论文23篇，会议论文7篇），其中SCI收录3篇，EI收录9篇，ISTP收录3篇，使我们的研究大大超额完成任务。

Unlike the conventional indirect method, it can directly implement the generator field and armature current limits accurately, thereby assuring power flow convergence and voltage collapse point identification during tracing the PV curve when generator limits constraints are considered. The critical limit constraint equation is introduced in the corrective stage of the continuation method as the additional equation to solve the limit induced bifurcation point accurately.

给出新的发电机电流极限约束的直接处理算法，解决了计及发电机电流约束时，潮流难于收敛和不易精确求出电压崩溃点的问题；对不易精确求得的极限诱导分岔点，通过在连续潮流法的校正步骤中将关键的极限约束方程作为附加方程来快速而精确地求解。

Chapter 4 deals with the three-unit ring network with self-feedback.We mainly focus on the bifurcation phenomena near the trivial solution.

在第四章中，我们主要讨论带自反馈的3元环状神经网络系统的平凡解对应超越特征方程的正实部根个数的变化规律以及该系统在平凡解附近的分岔性质。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。