Blow-Up Estimates for a Quasilinear Reaction-diffusion System

Recently,reaction-diffusion systems of the Fujita type ut=Δu+u m1vn1 vt=Δv+um2vn2，(x,t)∈Ω×(0,T)[ JY〗(A) as well as the related elliptic system -Δu=um1v n1， -Δv=um2vn2，x∈Ω (B) with Ω∈RN，mi,ni0,i=1,2 were studied by a number of authors.The p roblem concerning (A) includes global existence and global existence numbers,blo w -up,blow-up rates,and blow-up sets,uniqueness and nonuniqueness,etc. For (B) there are problems such as existence and nonexistence,uniqueness and nonuniquene ss,and so     

一类非线性波动方程组的爆破性质

作者研究了如下一类具初边值问题的相互作用波动方程组:utt -Δ(u+v)=f(u,v), t＞0,x∈Ω,vtt -Δ(u+v)=g(u,v), t＞0,x∈Ω,讨论了该方程组初边值问题解的爆破性质.     

全空间中一类椭圆方程组解的存在性

讨论了下面问题:{-Δu+qu=2αα+β|u|α-2u|v|β,x∈RN,-Δv+qv=2βα+β|u|α|v|β-2v,x∈RN,u,v∈H1(RN)。应用变分法证明了以上椭圆方程组至少存在一个非平凡的非负解。     

Isometry Between Two Indefinite Metrics

Introduction and TheoremGiven two indefinite metrics( quadratic) :I =Edu2 + 2 Fdudv + Gdv2 ,I=Edu2 + 2 Fdudv+ Gdv2 ( 1 )on regions D,D of a plane,the isometry problemis to decide whether there is a transformation:u=u( u,v) ,v=v( u,v) ( 2 )such that after substitutionI=I ( 3)　　The above problem is equivalent to theexistence of the solutions of the following firstorder PDE systems:E uu2 + 2 F uuvu+ G vu2 =E( u,v) ,Euuu…     

Pancyclism in Claw-free Graphs

IntroductionUsethegraphtheorywithapplications[1]forterminologyandnotationnotdefinedhereandconsidersimplegraphsonly.LetGbeagraphofordern.Foranya∈V(G),AV(G)orasubgraphAofG,andanysubgraphHofG,letNH(a)={v∈V(H):av∈E(G)},NH(A)=∪v∈ANH(v)=NH(V(A)).SetNG(a)=N(a),thedegreeofvbyd(v)=|N(v)|andΔ=max{d(u)|u∈V(G)}.Thedistance,denotedbyd(u,v),betweentwoverticesuandvofaconnectedgraphistheminimumlengthofallpathsjoininguandv.AgraphGiscalledclaw-freeifGhasnoinducedsubgraphisomorphictoK1,3.G…     

相互作用波动方程组整体解的爆破性

利用能量守恒定律和积分不等式技巧,讨论了相互作用波动方程组utt-Δ(u+v)=f(u,v),　vtt-Δ(u+v)=g(u,v),　t>0,x∈Ω整体解的爆破性,得到了关于系统爆破性的一些性质,并给出了blow up时间的一个界.     

Weighted inequalities in martingale spaces

We give a condition on the couple of weights(u,v) for Doob's operator to be a bounded one from martingale space Lp(u) to function space Lp(v) .Moreover,we also obtain necessary and sufficient conditions in order that the maximal geometric mean operator is bounded from martingale space Lp(u) to function space Lp(v) or Lp,∞(v) .     

全空间中椭圆方程组解的存在性

研究了下面椭圆方程组解的存在性问题{-Δu+qu=2α/α+β|u|~(α-2)u|v|~β,x∈R~N,-Δv+qv=2β/α+β|u|~α|v|~(β-2)v,x∈R~N,u,v∈H~1(R~N)。通过Nehari流形法证明了以上方程组具有非平凡解。     

三维空间中耦合非线性Schroedinger方程组的整体解

证明了三维空间中一类耦合非线性Schroedinger方程组的Cauchy问题 iut＋Δu=a｜u｜^a-1u｜v｜^β＋1，ivt＋Δv=b｜u｜^a＋1｜v｜^β-1v,u（0,x）=u0（x）,v（0,x）=v0（x）,t＞0，x∈R^n，整体解的存在唯一性，并得到了解关于初值的连续依赖性及解具有的较强的衰减估计     

一类合作型拟线性椭圆方程组多个解的存在性

利用Ekeland's变分原理和山路引理,考虑合作型拟线性椭圆系统-Δpu=λa(x)|u|p-2u+λ/β+1b(x)|u|α|v|βv+Fu(x,u,v),x∈Ω;-Δqu=λc(x)|v|q-2v+λ/α+1b(x)|u|α|v|βu+Fv(x,u,v),x∈Ω;u=v=0,x∈Ω在参数λ从左边无限接近于相应的非线性特征值问题的第一个特征值λ1时,系统有3个非平凡解.     

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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