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1.
证明四阶强阻尼非线性波动方程的初边值问题utt-Δu-αΔut-εΔutt+f(u)=0 (α≥0, ε>0),u(x,0)=u0(x), ut(x,0)=u1(x),u|Ω=0的整体广义解的存在惟一性. 利用"逐次磨光法"证明其整体W2,p与Wk,p的存在性, 并讨论其整体古典解的存在性.  相似文献   

2.
讨论了具有快速增长非线性项的Cahn-Hilliard方程ut г△^2u-△G(u)=0,G(u)=△↓^uφ(u),△↓^xun|x∈ЭΩ=△↓x(△u)n|x∈ЭΩ=0,u(0,x)=u0(x)解的长时间行为,构造了一个新系统,利用压缩映象原理,得到了该系统解的存在唯一性和一个m维光滑流形,即近似惯性流形,证明了Gahn-Hilliard方程的任意轨道在长时间后时入该流形的一个很小的领域中。  相似文献   

3.
研究了下列具有阻尼的非线性以曲型方程的Cauchy问题utt k1ux^4 k2ux^4t g(uxx)xx)=f(x,t) x∈R,t>0 (a) u(x,0)=ψ(x),ut(x,0)=ψ(x) x∈R (b)首先应用Galerkin方法和紧致性定量证明方程(a)的周期边值问题存在惟 的整体广义解和整体古典解,然后证明Cauchy问题(a),(b)存在惟一的整体广义解和整体古典解。  相似文献   

4.
当λ充分大时,研究含特征值退化椭圆型方程Dirichlet边值问题Di(g(|Du|2)Diu) λp(u)=0 x∈Ω/u=0 x∈(e)Ω的非平凡广义解问题,在一定的条件下证明上述边值问题至少存在一个非平凡广义解.  相似文献   

5.
本文给出了如下问题{div(|△↓u|^p-2△↓u)+λf(u)=0,x∈Ω/u|δΩ=0,奇异解的能量估计,其中p≥2,Ω=B1是单位球,λ〉0是一个参数.进一步得到了uλ是上述问题的正则正解序列且当λ→λ0∈(0,∞)时逐点收敛于奇异解U,则在L^q+1(B1)和H0^1(B1)中,当λ→λ0时uλ收敛于U。  相似文献   

6.
研究了拟线性椭圆型方程组div(|↓△u|^m-2↓△u)=p(|x )f(v),div(|↓△v|^n-2↓△v)=q(|x|)g(u)在R^N上爆破整体正对称解的存在性和解集的性质,其中f和g在(0,∞)上是正的递增函数,本文结果是新的且推广了所知结果。  相似文献   

7.
获得了Euler微分方程组-△ui(x)+N↑∑j=1Fpij(x,u(x),△↓u(x))+Fζi(x,u(x),△↓u(x))=hi(x),i=1,2,…,m在边界条件ui(x)|δΩ=0下存在广义解的一个充分条件,这里Ω∪→R^N(N≥3)是具有C^1边界的有界开区域,h∈L2N/N+2(Ω)^m。  相似文献   

8.
研究了Dirichlet问题 {-Δμu=:-div(|Δ↓u|^(μ-2)μ↓u)=λW(x)|u|^(μ-2)u|f(x,u),x∈Ω, u=0,x∈δΩ, 其中,Ω是R^n(n≥3)上的一个有界域,W(x)是一个不确定权值,通过局部环绕,证明在λ与W(x)满足适当条件下,该方程有弱解及无穷多解的存在性.  相似文献   

9.
通过周期边值问题序列的方法,证明了如下非线性波动方程{uu-uxx-uxxu=f(u)xx,x∈R,t〉0,u(x,0)=u0(x),ut(x,0)=u1(x),x∈R的Cauchy问题整体广义解和整体古典解的存在性和惟一性,并利用凸性引理给出这个问题解爆破的充分条件.  相似文献   

10.
一类半线性抛物型方程解的blow—up   总被引:2,自引:2,他引:0  
设Ω R”的有界区域,u(x,t)是问题:u_t-△u=f(u)在Ω×(0,T),β u/ v+u=g(u),β>0,在Ω×(0,T),u(x,0)=u_0(x)的古典解此地△是n维的Laplac, u/ v记为u在Ω的外法向,利用凸性方法证明了上述问题的解在有限时间内变无穷,其中f(u),g(u)和u_0(x)满足以下不等式集合的任一个: (d_1) u_0(x)≥0,f(u)≥0,g(u)≥0,u_0(x) 0,△u_0+f(u)>0,uf'(u)-(l-1)f(u)≥0,ug'(g)-(l-1)g(u)+(l-2)u≥0,l>2。 (d_2) u_0(x)≥0,f(u)≥0,g(u)≥0,△(u_0)+f(u_0)>0,f'(u)-αf(u)≥0,g'(u)-αg(u)+αu-1≥0,α≥0。 (d_3) u_0f(u_0)≥0,u_0(x) 0,uf'(u)-(2α+1)f(u)=0, 对于任意实数W,integral from n=0 to W[(z(g(z)+2α)-(2α+1)g(z)]dz≥0,α>0,∫Ω(integral from n=0 to u_0 1/β(g(z)-z)dz)dx-1/2∫Ω|▽u_0|~2dx>0。  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
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。  相似文献   

14.
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.  相似文献   

15.
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-  相似文献   

16.
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-  相似文献   

17.
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  相似文献   

18.
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  相似文献   

19.
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  相似文献   

20.
<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  相似文献   

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