四圆盘扭振系统三重共振理论研究

研究受简谐激励作用发电机组转子轴系扭振模化系统的固有频率存在的双重内共振关系ω３≈２ω２,ω２≈２ω１,且Ω≈ω１时的三重共振问题,求得了系统三重共振的一次近似解及稳态响应曲线,指出系统具有多解共存现象。     

广义Van der Pol型强非线性共振的转迁集

运用改进的Ｌ－Ｐ方法,引入参数变换α＝εｑ２ω１／（ｐ２ω２０＋εｑ２ω１）,用多尺度法求出广义ＶａｎｄｅｒＰｏｌ型强非线性主振、亚谐、次谐共振的分岔响应方程和转迁集,得出主振、ｋ≠１／２时的亚谐、次谐振动具有相同的分岔拓扑结构,而ｋ＝１／２时的亚谐振动的分岔结构更加复杂     

多滞量的反应扩散方程的分支环（I）：谨以此文庆贺肖伊莘先生八十大寿

本研究一类定义在单位圆周上带有两个时滞的纯量反应扩散方程，在一定条件下，我们证明了方程在鞭平凡解处的线性化有一对简单的纯虚特征值±ｉω１，和一对重的纯虚特性值±ｉω２，且是非共振的（即ω１／ω１是无理数），然后，应用［３］的中心流形的方法得到了一个六维常微分方程，用它来刻划方程在其平凡解邻域内的解的渐近性态。     

RLC电路弹簧耦合系统的非线性动力学分析

通过拉格朗日-麦克斯韦方程，建立了受到简谐激励作用的RLC—S耦合系统的数学模型，该系统具有平方非线性。应用非线性振动的多尺度法，发现在内共振ω2≈2ω2，双重共振ω2≈2ω1且Ω≈ω2两种情况下，系统具有丰富的动力学现象。运用Matlab软件进行数值运算，得到的结论对实际的工程应用具有指导价值。     

关于2^ω〈2^ω1的等价刻划

本文证明了“２＾ω〈２＾ω１”与“每一正规、χ（Ｘ）≤２＾ω，ｔ（Ｘ）≤ω局部ＤＣＣＣ次亚Ｌｉｎｄｅｌｉｆ空间仿紧”是等价的，从而使关于２＾ω〈２＾ω１的等价刻更趋于完整。     

声波驱动下气泡群的非线性共振

由于次级声辐射的影响,泡群内的气泡处于群振动状态.基于气泡耦合振动方程,利用逐级近似法分析了气泡非线性声响应,得到了基频成分、一阶和二阶谐频成分、一阶和二阶次谐频成分的幅频关系式,并以此为基础分析了气泡在基频共振区(ω≈ω0)、一阶和二阶谐频共振区(ω≈ω0/2,ω≈ω0/3)的声响应特征.数值分析表明:泡群内气泡数密度以及气泡初始半径对其共振声响应影响显著,而气泡在泡群内所处的相对位置影响相对较小.气泡的次谐频共振(ω≈2ω0,ω≈3ω0)只有在驱动压力幅值超过一定阈值后才可能发生,且压力阈值随着气泡初始半径的增加而减小.     

氢键链中外场对扭结孤子和呼吸子的影响

利用导数展开法，分别研究了在氢键链中外场对于扭结孤子和呼吸子的影响，得到了孤子迁移率及其共振频率，并指出当外场频率ω０满足时，呼吸子发生相锁。当ω０＝ωＨ时，扭结孤子作共振运动．     

钙蒸气中的紫外相干辐射特性研究

用氮分子激光器泵浦的两台染料激光器(输出光频率分别为ω_1和ω_2)二步激发钙蒸气,由不等频二步共振和不等频双光子共振四波混频ω_1+ω_2-ω_(IR)=ω_(UV)(ω_(IR)为红外受激辐射频率),产生了波长为272.2nm的紫外相干辐射,并对其激发和辐射特性进行了研究.     

一类插值多项式逼近

设ｎ是偶数，Ｐｎ－１是Ｌｅｇｅｎｄｒｅ多项式，Ｒｎ（ｆ，ｘ）是以（１－ｘ＾２）Ｐｎ’－‘１（ｘ）的零点为基点的所谓（０，２）型插值多项式，本文构造了两个函数类Ｈω２，Ｈω１，研究了Ｒｎ（ｆ，ｘ）逼近Ｈω２，Ｈω１中函数ｆ（ｘ）的阶。     

电子在特殊摆动器中运动的辐射

本文根据电子在与Ｚ轴无关磁场的摆动器中的运动，分析、计算了运动电子的自发辐射。最后结果中包含一个重要因子（ｓｉｎη／η）＾２，它把自由电子的受激辐射与自发辐射联系起来了，结果说明，当△ω＝０，即在共振情形下，电子在磁场与Ｚ轴无关摆动器中的自发辐射消失。     

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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