利用测度同步实现对耦合哈密顿Duffing系统的混沌控制

利用测度同步现象对耦合Duffing哈密顿系统的混沌进行了控制.结果表明,该控制方法简单、明了,控制效果好,并在控制过程中不改变系统的保守性.     

Henon-Heiles体系的混沌控制

分析了不可积哈密顿系统混沌控制的LDG方法,并利用它实现了对Henon-Heiles体系周期1轨迹的混沌控制,通过实例分析了该方法的优点和局限性.     

强迫弦振动的不规则波长驻波与混沌

介绍强迫弦振动的不规则波长驻波与实验观测结果.对于一端固定,另一端受到简谐驱动的弹性弦,可以产生不规则波长的驻波振动,从而会发生波长不等于整数倍的二个驻波振动的"争夺"振动,出现混乱振动.给出了混沌振动轨迹的实验测量方法和结果.     

由稳定流型和不稳定流型证实氢原子的粘性效应

本文研究了氢原子哈密顿系统暴露在强激光场下的粘性效应，即使对于单电子系统，其庞加莱截面也显示出了由激光场引起的混沌部分和规则部分，并可以用KAM理论来解释.通过变分方法对混沌“海”中的不稳定周期轨道进行了寻找，并数值求解了相应的稳定流形和不稳定流形.研究结果表明，单电子系统电离的动力学性质由不稳定周期轨迹控制.一方面，不稳定周期轨迹的稳定流形很好地与递归图叠加在一起，表明稳定流形只与相空间中稳定的初始点重叠.另一方面，不稳定流形几乎与庞加莱表面上密集分布的点重合.这表明不稳定流形只是通过激光场驱动轨迹演化的电离通道.此外，在稳定流形与不稳定流形相互穿插的不稳定岛附近的不同区域的存活概率也被深入研究.它们服从代数衰减规律.相同的衰减趋势也出现在不稳定流形上，它们具有与不稳定周期轨迹附近区域相近的衰减参数.这些观察证实了不稳定周期轨迹的稳定性对在KAM稳定岛附近相空间的粘滞效应起着非常重要的作用.     

低阶混沌电路非线性动力学特性的实验研究

通过实验对二阶非自治混沌电路、三阶蔡氏电路和四阶非自治混沌电路进行了详尽研究,证明这些电路能够产生复杂的非线性动力学行为.以电路实验数据为依据,首次绘制出两个混沌电路的稳定岛图.     

具有双向耦合的混沌系统的完全同步

对具有双向耦合的混沌系统,首先通过广义哈密顿系统和观测器的方法重新设计;其次利用Lyapunov稳定性理论对其误差系统的零解稳定性进行研究,得到了完全同步的条件;最后将该方法应用到洛伦兹系统,数值结果也表明了该方法的正确性.     

二维混沌哈密顿体系的逃逸率

研究二维混沌哈密顿体系的逃逸率在逃逸阈值附近的规律.对Hénon-Heiles系统添加一个势垒,通过改变势垒的位置、宽度、高度等参数可以产生一系列混沌体系.对这些体系的逃逸率随体系能量变化的解析公式和数值计算提取的结果一致,并可以用参数化公示表达.在阈值附近,这些体系的逃逸率随能量的增加总是呈现线性关系.结果提供了进一步的证据,证明有光滑开口的二维保守混沌体系的逃逸率随能量线性增加可能是普适结论.     

具有隐藏吸引子的混沌系统的动力学分析

对一个具有隐藏吸引子的混沌系统进行了基本的动力学分析,找出了系统的平衡点,通过分岔图与Lyapunov指数分析了参数对该系统动力学行为的影响.利用Matlab软件仿真出系统的相图,分析了系统的吸引子是隐藏的.最后,求得该系统的哈密顿能量函数,验证了能量函数的正确性,并对系统的能量转移进行了讨论.     

无平衡点的混沌系统的动力学分析与能量反馈控制

通过向具有无穷多个平衡点的混沌系统引入新的参数的方法,提出了一类新的混沌自治系统,该系统的最大特点是没有平衡点,因此其所有的动力学行为都是隐藏的.利用理论分析、Lyapunov指数和分岔图等非线性系统分析方法,研究了该新系统随着新参数变化时,1周期、2周期及混沌等复杂的隐藏动力学行为.另外,当初始条件不同时,新系统存在极限环和混沌吸引子共存的现象.最后,通过计算系统的哈密顿能量,设计出能量反馈控制器,在一定时间内将混沌消除.     

混沌吸引子的普适转变

二维动力学映射混沌吸引子的片结构将随耗散性的减弱以普适的方式截断,最终趋于哈密顿极限。不稳定不变流形的异宿相交可以解释混沌吸引子片结构的突变行为,突变点具有普适的标度,哈密顿映射对于耗散方向的重正化理论可以给出这一普适标度。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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