非线性微分方程三阶三点边值问题正解的存在性

三阶微分方程有着广泛的应用背景和重要的理论价值,格林函数在三阶三点边值问题的正解存在性理论中有着重要作用,考虑三阶三点边值问题{u(t)+a(t)f(u(t))=0, t∈(0,1),u(0)=u″(0)=0, u'(1)=αu(η),其中0<η<1, 0<α<1/η。 通过建立相关线性边值问题的格林函数得到解的形式,运用不动点指数理论建立上述边值问题至少两个正解的若干存在性准则。     

一类非线性三阶边值问题正解集的全局结构

考虑一类非线性三阶常微分方程边值问题{-u⁽³⁾(t)=λf(t,u(t)), a.e. t∈［0,1］,u(0)=u'(0)=0, u'(1)=αu'(η)正解集的全局结构,其中 f:［0,1］×R→［0,∞)为L1-Carathéodory函数,0<η<1 且 1<α<1/η为常数。在f满足线性增长的条件下,运用Rabinowitz全局分歧定理得到其正解集的全局结构。     

奇异二阶三点边值问题的一个正解存在定理

考察了二阶三点边值问题{u"(t)+h(t)f(t,u(t))=0,0相似文献   

非线性微分方程三阶三点边值问题一个正解的存在性

格林函数在三阶三点边值问题的正解存在性理论中有着重要作用.考虑以下三阶三点边值问题{u''(t)+a(t)f(u(t))=0,t∈(0,1),u(0)=u″(0)=0,u'(1)-αu(η)=λ,其中,0η1,0α1/η,参数λ∈(0,∞).通过建立相关线性边值问题的格林函数得到解的形式,运用Guo-Krasnoselskii不动点定理建立上述边值问题至少一个正解的存在性准则.     

非线性微分方程三阶三点边值问题两个正解的存在性

考虑以下三阶三点边值问题:u''(t)+a(t)f(u(t))=0,t∈(0,1);u(0)=u″(0)=0,u'(1)-αu(η)=λ,其中0η1,0α1/η,λ∈(0,∞),通过建立相关线性边值问题的格林函数得到解的形式,运用不动点指数理论建立了上述边值问题至少两个正解的存在性准则.     

一类奇异二阶三点边值问题的正解存在性

考察了二阶三点边值问题{u"(t)+h(t)f(t,u(t))=0,a e t∈[0,1], u(0)=0,au(η)=u(1),的正解存在性,其中0<η<1,0<αη<1,h∈L[0,1]并且允许f(t,u)在u=0处奇异,通过利用Guo-Krasnosel'skii不动点定理获得了一个正解存在定理.     

一类非线性三阶三点边值问题正解的存在性、不存在性及多解性

考虑一类非线性三阶三点边值问题{u(t)+λf(t,u(t))=0, t∈［0,1］,u(0)=u'(0)=0, u'(1)=αu'(η)正解的存在性、不存在性以及多解性,其中λ>0是一个参数,0<η<1, 1<α<1/η, f:［0,1］×［0,∞)→(0,∞)是一个连续函数。主要定理的证明基于不动点指数理论、Leray-Schauder度以及上下解方法。     

超线性条件下二阶三点边值问题正解的存在性

运用Green函数和锥上的不动点定理,讨论了二阶奇异三点边值问题-u″(t)=α(t)f(u),0相似文献   

一类三阶三点边值问题的正解的存在性

讨论边值问题Lu:=u (t)=f(t,u(t)),u(0)=u′(η)=u″(1)=0,0≤t≤1,12≤η<1的正解的存在性.设λ1为Lu=λu在相应边值条件下的第一特征值,f(t,u)≥0在[0,1]×[0,∞)上连续,f(0,0)=0,在超线性和次线性条件下,得到边值问题正解存在的一个新结果.     

三阶微分方程三点边值问题正解的存在性

考虑以下三阶三点边值问题:{u''(t)+f(t,u(t))=0,t∈(0,1),u'(0)=u″(0)=0,u(1)=αu(η),其中0η1,0α1.通过建立相关线性边值问题的格林函数得到解的形式,运用不动点指数理论建立了上述边值问题的正解的存在性准则.     

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.     

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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