一类测度微分方程解的有界性

研究一类测度微分方程解的有界性,借助测度微分方程与广义常微分方程的等价关系,利用广义常微分方程解的有界性定理建立了测度微分方程解的有界性定理.     

n维空间的全微分方程的求解

本文从通常的常微分方程出发,考虑了n维空间的全微分方程,得出了n维空间全微分方程的充要条件。     

模糊微分方程可约的条件

模糊微分方程是在模糊环境下研究动态系统的重要工具,所以对方程进行求解是一项必不可少的工作.为了能使更多的模糊微分方程更容易求解,通过对非线性模糊微分方程进行变量替换判断方程是否可约,并在此过程中试图找到非线性模糊微分方程转化成线性模糊微分方程的方法.最后给出了2种形式的模糊微分方程是否可约的充分条件,同时推导出非线性模糊微分方程转化为线性模糊微分方程的具体方法,使可约模糊微分方程更容易辨别和求解,并且给出算例验证了结果的有效性.     

非线性脉冲时滞微分方程的线性化振动

研究了一类非线性脉冲时滞微分方程的振动性．证明了在一定条件下,可以由线性脉冲时滞微分方程的振动性判定非线性脉冲时滞微分方程的振动性．得到了非线性脉冲时滞微分方程与相应的线性脉冲时滞微分方程振动性等价的条件,并给出了它的应用。     

一维二阶线性微分方程的基本解

本文对于一维二阶线性微分方程(即常微分方程)定义并构造了J.Hadamard的基本解,从而推广了变量分离的二阶线性偏微分方程的基本解的构造定理[3],使得可以用常微分方程的基本解来构造一系列偏微分方程的基本解。     

二阶模糊微分方程的数值解

研究了二阶模糊微分方程的数值解,给出并证明了二阶模糊微分方程的2个特征定理,利用特征定理二阶模糊微分方程可以转化为微分方程组,从而求得二阶模糊微分方程的解。     

具有非单调项的二阶微分方程的振动准则

主要利用降阶法,得到具有非单调项的二阶微分方程振动的充分条件.首先根据降阶法及相关的不等式知识,将带有非单调项的二阶微分方程转变为一阶微分方程.之后运用具有非单调项的一阶微分方程已知的相关结果,得到了二阶微分方程的振动准则,改进了以往的二阶微分方程解的振动结果.最后通过例题说明所得结论的可应用性.     

高阶变系数线性微分方程的解

本文给出了广义全微分方程的定义,得到了高阶变系数线性微分方程化为全微分方程的充要条件和通解计算公式.     

线性微分方程的有限差分法求解周期正解

为了提高线性微分方程在求解计算中的性能，提出了线性微分方程的有限差分法求解周期正解。证明了线性微分方程的有限差分格式与能量守恒的离散规则是等价关系，分析了线性微分方程差分格式的正性和周期性，实现了基于有限差分法的线性微分方程求解周期正解。最后通过数值实验的方式，得出与传统差分法求解线性微分方程的周期正解相比，不仅满足了正性要求，还满足了周期性要求。     

几类泛函微分方程的稳定性比较研究

泛函微分方程是对各种具有复杂变元的微分方程和带有各种滞后量的积分微分方程等的抽象概括,其稳定性研究在现代化的科学研究中具有重要的作用;在此,就中立型泛函微分方程、非线性泛函微分方程和随机时滞泛函微分方程的稳定性进行了探讨;不同类型的泛函微分方程采用的数值方法尽管有相似之处,但也有一些区别;无论哪种方法,都旨在为泛函微分方程的稳定性研究提供可靠的理论保障。     

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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