二阶非线性中立型微分方程的振动性

考虑二阶中立型时滞微分方程（r（t）Ф（x（t））[x（t）＋p（t）x（τ（t））]′＋F（t，x（t），x（σ（t）），x′（t），x′（σ（t）））=0利用广义Riccati变换得到了方程所有解振动的充分条件．     

偶数阶中立型微分方程振动性的比较结果

考虑偶数阶中立型时滞微分方程（r（t）（x（t）＋p（t）x（τ（t））^（n-1）′＋F（t，x（t），x（σ（t）））=0建立了方程与某一阶时滞微分方程振动性之间的比较结果．     

一类具脉冲的时滞泛函微分方程的全局吸引性

考虑具有脉冲的时滞泛函微分方程{ x＇（t）＋a（t）x（t）=p（t）（I-e^x（t-t））,t≥0,t≠tk, x（t k^＋）-x（tk）=bk x（tk）,k∈N 其中a（t），p（t）∈C（[0,＋∞）,[0,＋∞））,τ〉0,bk〉-1,k∈N获得了方程每一解x（t）满足lim t→∞ x（t）=0的充分条件，将结果应用于脉冲方程及脉冲的红血球生长模型，所得结果是新的．     

Liénard方程反周期解的存在性与唯一性

利用Leray-Schauder度理论研究二阶Lienard方程：x″（t）＋f（x（t））x′（t）＋g（t，x（t—τ（t）））=p（t）反周期解的存在性和唯一性．     

一类非线性脉冲时滞差分方程的振动性

研究了如下具有脉冲的非线性多时滞差分方程{x（t）-x（t-τ）＋p（t）f（x（t-σ））=0, t≥0,t≠tk x（tk^＋）-x（tk）=bk x（tk）.t=tk,k=1,2,…利用构造函数，通过反证法、单调有界原理及极限与求和的方法得到了方程振动的两个充分条件，对已有文献中的某些结果进行了推广和改进．     

三阶非线性中立型微分方程非振动解的渐进性

考虑三阶非线性中立型时滞微分方程（r2（t）（r1（t）（x（t）＋p（t）x（τ（t）））′）′）′＋q（t）f（x（t），x（σ（t）））=0利用积分平均法得了方程的有一个有界非振动解x（t）满足lim（t）t→＋∞=0的一个充分条件，所得结果改进并完善了以前的结论．     

具偏差变元的p—Laplacian方程的周期解问题

利用重合度拓展理论研究了一类具偏差变元的p-Laplacian方程（φp（x″（t））″）＋f（x″（t））＋g（t,x（t-τ（t））=e（t）的周期解问题，得到了其解的存在性．     

初边值条件下一维非齐次BBM方程的整体吸引子

研究了一维非齐次方程BBM方程u1-uxx1-（u^11）x-g（x）-f（u）＋uxx,ux（0,t）：0，u（1，t）=0;u（x，0）=u0（x）的初边值问题，利用Sobolev插值不等式，对解做关于时间t的一致性先验估计，证明了该问题的整体吸引子的存在性．     

一类二阶非线性积分一微分方程属于极限圆型的判定

研究了方程（r(t)x‘)‘_a(t)x=0(*)和二阶积分微分方程（r(t)x‘)]( (a(t) b(t))x=f[tx(t),t0g(s,x(s),ds],t≥0(**)按极限圆型的分类问题，在一定条件下方程（**)与方程（＊）具有一致的极限圆型。     

二阶非线性微分方程的振动准则

本文主要讨论二阶非线性微分方程（r（t）x’（t））’＋p（t）f（x（t））g（x’（t））=0得到方程的一些新的振动准则．这些结果改进了Wintner，Hartman，Kamenev，Yan和Philos利用通常的黎卡提变换u（t）=a（t）r（t）{x＇（t）/x（t）＋k（t）），其中k∈C^1是[t0，∞）上的连续函数，和a（s）=exp{-2}k（ξ）dξ}所得的振动准则．     

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.     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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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