马尔可夫过程的几可乘泛函及伴随的转移概率变换

§1引言本文沿用[1]、[2]中的记号和定义.设α_t(ω)(0≤t<ξ(ω))是齐次马尔可夫过程X=(x_t,(?),M_t,P_x)的几压缩几齐次几可乘泛函(详细定义见后),则(?)(t,x,Γ)=M_x(XΓ(xt)α_t)(t≥0,x ∈E,Γ∈(?))定义相空间(E,(?))上一转移函数.从直观看来,这相当于以一定的规律缩短原过程的生命而得到一新的转移函数,α_t 给出在时间区间[0,t]内生命不缩短的概率.(?)(t,x,Γ)对应的半群算子是     

广义Logistic型泛函微分方程零解的全局吸引性

研究广义Logstic型泛函微分方程x′(t)+[1+x(t)]F(t,x[·]α)=O(t≥O,α≥1)零解的全局吸引性.运用一些分析方法和技巧,对该方程的零解作出估计,得到方程零解是全局吸引的一些充分条件,结果推广并改进了现有文献中的相关结论.     

微分方程零解的全局稳定和全局渐近稳定的充要条件

本文讨论扰动矢量方程dx_。,.’、—‘I、t,X少dt(1)其中:x=(x,,xZ,……,x。)堤R”空I’ed的矢量,f(t,x)是定义在I火Rn空l’ul 0(t<+co,}lx{l<+二(2)上的n维连续矢量函数,f(t,。)三。,满足解的存在及唯一性条件,并且假定解可以开拓到t二+co。 约定x二x(t;x“,t。)表示方程(1)满足初始条件x(t。)二x“的解。 本文的目的在于提出微分方程(1)的零解全局稳定和全局渐近稳定的充要条件。 定理1方程(1)的零解x二O全局稳定·‘的充要条件是:在1 XR“空间 t)t。.{{x}}<+co(3) 内存在无限大定正函数V(t,x),满足条件 V(t,x(t;x“,t。))(V(t。,x…     

一类含时滞的奇异微分积分方程的稳定性分析

本文主要讨论一类具有时滞的奇异微分积分方程Ex(t)=Ax(t)+f(t,x(t),x(t-r(t)))+∫/t-rg(t-s,x(s))ds,t≥t0,其中,[f(t,x,y)]+≤B[x]+L[y]+,[g(t-s,x(s))]+≤H(t-s)[x(s)]+.首先,阐述本文研究背景和意义,给出奇异微分积分方程指数稳定、Dini导数和M-矩阵的定义,以及一些必要的数学记号的含义.然后,利用分析技巧和方法并结合M-矩阵的性质,建立一个广义时滞微分积分不等式.最后,借助于建立的广义微分积分不等式,获得了含时滞的奇异微分积分方程零解全局指数稳定的一个充分条件,即当D∈M,D=-(A+B+L+r∫0H(s)ds),那么方程的零解是全局指数稳定的.     

一类泛函微分方程零解的全局吸引性

通过不等式的推导,研究广义Logistic型泛函微分方程x＇(t)+[1+x(t)]F(t,x[·])=0零解的全局吸引性.其中:t≥0,0＜α≤1且α为两正奇数之比,F(t,Φ)是[0,+∞)×Ct上的连续泛函.将所得到的结果运用到方程讨论中,改进并推广了其他文献的一些结果.     

一类非线性二阶微分方程全局渐近稳定的充要条件

本文研究如下一类二阶非线性方程(组)全局稳定的充要条件(Ⅰ)(a(t)x')' p(t,x,x')f(x)φ(x') q(t)g(x)h(x')=e(t,x,x')约定上述方程或方程组中出现的函数均在区域t≥0,|x| |y|<∞连续     

二阶微分方程全局渐近稳定性的充要条件

在适当的条件下研究二阶微分方程 x+p(x,x,t)f(x)Φ(x)+q(t)g(x)h(x)=e(x,x,t)及其特殊方程的零解x=x=0为全局渐近稳定的或一切解及其导数均趋向于(0,0)的充要条件。并在具有无界阻尼的条件下,对p(x,x,t)给出一个增长条件,以保证其零解为全局渐近稳定或一切解及其导数均趋向于(0,0)。     

两类三阶非自治系统的全局渐近稳定性

利用L iapunov函数法,给出两类方程…x g(x。)x。 bx。 f(x)=e(t,x,x,。x。)和…x g(x。)x。 f(x)x。 cx=e(t,x,x,。x。)零解全局渐近稳定性的充分条件,推广文献[1~4]中的相关结论.     

一类微分差分方程的周期解和全局吸引性

讨论一类微分差分方程 x(t) =gradG(x(t) ) +f(t,x(t-r) )的周期解问题 ,其中x(t) =(x1(t) ,… ,xn(t) ) T 是n维连续向量 ,G(x)为连续可微函数 ,r>0 ,f(t,x)是n维连续向量函数 ,且f(t+ω ,x) =f(t,x) ,ω>0。利用重合度理论中的延拓定理并构造Lyapunov泛函得到了周期解的存在性和全局吸引性定理。改进并扩充了文 [3]的有关结果。     

Hamilton群上的H圈问题

设G是有限群,(?)是G的Cayley—子集.用X(G,(?))表示G关于(?)的Cayley图,其中V(X)-G,E(X)-{((?),)|(?)∈G,(?)∈(?)),本文证明了:对于(?)ilton群G,若X(G,(?))是连通的,则X(G,(?))有Hamiltonian(?)另外.本文也对有限交换群情形给出一个简单证明。     

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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