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1.
讨论可加稳定分量过程局部时的存在性和连续性,证明了在N>max1≤k≤N∑hl=1dlαlk条件下,N指标可加稳定分量过程X={X(t);t∈RN }a.s.存在关于时间变量t和空间变量x联合连续的局部时.  相似文献   

2.
设X={X(t),t∈RN }为以d×d可逆矩阵B为指数的N指标Rd值算子稳定Lévy过程,讨论了X在R N的子区域上的像集Hausdorff维数问题,证明了dim X([1,2]N)=min{d,αkN sum from j=1 to k dj(1-αk/αj),k=1,…,p},a.s.,其中α1>α2>…>αp为B的p个不同的特征值实部的倒数,d1,…,dp分别为它们所对应子空间的维数.该结论表明X在R N的子区域上像集Hausdorff维数完全由B的特征值的实部来确定.  相似文献   

3.
在无界区域上考虑了如下具有线性记忆项的半线性耗散波动方程的整体吸引子的维数估计 (utt + ±ut ? k(0)á(x)¢u ?R10 k0(s)á(x)¢u(t ? s)ds + ?f(u) = h(x); (x; t) 2 RN £ R+; u(x; t) = u0(x; t); ut(x; 0) = @tu0(x; 0); x 2 RN; t · 0: 其中N ? 3, ± > 0, 并á(x)?1 =: g(x) 2 LN=2(RN)TL1(RN). 为了克服在无界区域中与微分算子á(x)¢的非紧性有关的困难, 引入了能量空间X0 = D1;2(RN) £ L2 g(RN) £L21(R+;D1;2(RN)). Hausdorff维数维数和分形维数的估计是根据特征方程?á(x)¢u =au; x 2 RN的特征值a 分布的渐近估计得出的.  相似文献   

4.
IntroductionWeconsidertheinitialvalueproblemofNstiffdifferentialequations:y′=f(y)y(t0)=y0(1)withasufficientlysmoothfunctionf:RN→RN.Sincethefunctionfisindependentoft,system(1)wascalledautonomoussystem.Becausesystem(1)isastiffsystem,usuallyweuseimplicitmethodstosolvethem.ImplicitRunge-Kuttamethodandimplicitlinearmultistepmethodarewidelyusedtosolveproblemslikesystem(1),butbothofthemhavetheirowndrawbacks:implicitlinearmultistepmethodcan'tkeepgoodstabilitywhileitsorderbecomehigh(thehighestorde…  相似文献   

5.
设X是实数域或复数域F上维数大于1的Banach空间,Ф:B(X)→B(X)是一个可加映射。证明了如果存在正整数m,n使得(m+n)Ф([A,B])=m[Ф(A),B]+n[A,Ф(B)]对任意A,B∈B(X)且AB=P(其中P∈B(X)是一个固定的非平凡幂等元)成立,则存在λ∈F及在AB=P的换位子上为零的可加映射h:B(X)→F使得对任意A∈B(X),有Ф(A)=λA+h(A)I.  相似文献   

6.
对无界域RN上部分耗散的反应扩散方程给出了解的先验估计,通过引进适当的截断函数,当x、t充分大时,证明了解(u(x,t),v(x,t))一致小.利用连续半群全局吸引子的存在性理论,证明了有界吸收集的存在性,研究了解的渐近行为,解半群在L2(RN)×L2(RN)中是渐近紧的,得出了半群在L2(RN)×L2(RN)中全局吸引子的存在性.  相似文献   

7.
讨论了赫尔斯特参数H>1/2的一个可加分式布朗运动,其中漂移系数不连续的随机微分方程弱解的存在性,并根据分式布朗运动条件下的Girsanov定理证明了这个结果.  相似文献   

8.
主要研究半线性抛物方程ut=Δu+V(x)|u|p-1u爆破解的渐近行为.在本文中,假设N≥3并且1pN+2/N-2,初始值是有界的,V(x)∈C1(RN),且对任意x∈RN存在常数c和C使得c≤V(x)≤C成立.则当t→T时,对RN中的任意点a,(T-t)p1-1u(a+y(T-t)~(1/2),t)趋向于0或者±V(βa)β,(β=p-11).  相似文献   

9.
设X为实或复数域F上维数大于1的Banach空间, φ:B(X)→B(X)是一个可加映射。 证明了如果存在正整数m,n使得(m+n)φ([A,B])=m[φ(A),B]+n[A,φ(B)]对所有A,B∈B(X)成立, 则存在λ∈F及在换位子为零的可加映射h:B(X)→F使得对任意A∈B(X), 有φ(A)=λA+h(A)I。  相似文献   

10.
假设B^H=( B1^H,B2^H…,Bd^H )是一个Hurst指数0〈H〈1的d-维分数布朗运动,而 √(B1^H)2+)(B2^H)2+…+(Bd^H)2 分数Bessel过程。考虑过程X^H={X^H(t),f≥0}, X^H(t)=d∑j=1∫ο^ι Bj^H(S)/R^H(s)dBi^H(s)证明这个过程的局部时存在,并且建立了Tanaka公式。作为一个结论给出了该过程的局部时与1-维分数布朗运动的赋权局部时之间的一个等式。  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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