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1.
Random attractors for non-autonomous fractional stochastic Ginzburg-Landau equations on unbounded domains 下载免费PDF全文
This paper deals with the dynamical behavior of solutions for non-autonomous stochastic fractional Ginzburg-Landau equations driven by additive noise with $\alpha\in(0,1)$. We prove the existence and uniqueness of tempered pullback random attractors for the equations in $L^{2}(\mathbf{R}^{3})$. In addition, we also obtain the upper semicontinuity of random attractors when the intensity of noise approaches zero. The main difficulty here is the noncompactness of Sobolev embeddings on unbounded domains. To solve this, we establish the pullback asymptotic compactness of solutions in $L^{2}(\mathbf{R}^{3})$ by the tail-estimates of solutions. 相似文献
2.
The existence of random $\mathcal{D}$-pullback attractors for random dynamical system and its applications 下载免费PDF全文
In this paper, we establish a result on the existence of random $\mathcal{D}$-pullback attractors for norm-to-weak continuous non-autonomous random dynamical system. Then we give a method to prove the existence of random $\mathcal{D}$-pullback attractors. As an application, we prove that the non-autonomous stochastic reaction diffusion equation possesses a random $\mathcal{D}$-pullback attractor in $H_0^1$ with polynomial growth of the nonlinear term. 相似文献
3.
The Upper Semicontinuity of Random Attractors for Non-Autonomous Stochastic Plate Equations with Multiplicative Noise and Nonlinear Damping 下载免费PDF全文
Based on the existence of pullback attractors for the non-autonomous stochastic plate equations with multiplicative noise and nonlinear damping defined in the entire space $\mathbb{R}^n$ by Xiaobin Yao in \cite{Yao4}, in the paper, we further investigate the upper semicontinuity of pullback attractors for the problem. 相似文献
4.
杨昭 《数学年刊A辑(中文版)》2011,32(2):237-244
设π:M~n→P~n是P~n上的小覆盖,S是P~n的任意一个n-1维截面.给出了π~(-1)(S)是n-1维闭子流形(或者两个相互同胚n-1维闭子流形的不交并),以及π~(-1)(S)是n-1维伪流形的充要条件. 相似文献
5.
冯保伟 《数学年刊A辑(中文版)》2016,37(1):15-30
讨论了一类带有初值条件和固定边界条件的非线性非自治可伸缩板方程u_(tt)+△~2u+αu-△u_(tt)-M(||▽u||~2)△u-γ△u_t+f(u)=σ(x,t)证明了该系统的整体适定性.进一步研究了该系统的长时间动力学,利用建立整体弱解所生成的半过程一致渐近紧性,得到了有界区域Ω■R~n(n≥1)或无界开集中一致吸引子的存在性. 相似文献
6.
Regularity of pullback attractors for non-autonomous stochastic coupled reaction-diffusion systems 下载免费PDF全文
We consider the dynamical behavior of the typical non-autonomous autocatalytic stochastic coupled reaction-diffusion systems on the entire space $\mathbb{R}^n$. Some new uniform asymptotic estimates are implemented to investigate the existence of pullback attractors in the Sobolev space $H^1(\mathbb{R}^n)^3$ for the three-component reversible Gray-Scott system. 相似文献
7.
Metric n-Lie algebras have wide applications in mathematics and mathematical physics. In this paper, the authors introduce two methods to construct metric (n+1)-Lie algebras from metric n-Lie algebras for n≥2. For a given m-dimensional metric n-Lie algebra(g, [, ···, ], B_g), via one and two dimensional extensions £=g+IFc and g0= g+IFx~(-1)+IFx~0 of the vector space g and a certain linear function f on g, we construct(m+1)-and (m+2)-dimensional (n+1)-Lie algebras(£, [, ···, ]cf) and(g0, [, ···, ]1), respectively.Furthermore, if the center Z(g) is non-isotropic, then we obtain metric(n + 1)-Lie algebras(L, [, ···, ]cf, B) and(g0, [, ···, ]1, B) which satisfy B|g×g = Bg. Following this approach the extensions of all(n + 2)-dimensional metric n-Lie algebras are discussed. 相似文献
8.
Xiangzhi CAO 《数学年刊B辑(英文版)》2017,38(5):1071-1076
This paper deals with the p-harmonic function on a complete non-compact submanifold M isometrically immersed in an (n + k)-dimensional complete Riemannian manifold (M) of non-negative (n-1)-th Ricci curvature.The Liouville type theorem about the p-harmonic map with finite Lq-energy from complete submanifold in a partially nonnegatively curved manifold to non-positively curved manifold is also obtained. 相似文献
9.
《数学物理学报(B辑英文版)》2020,(4)
In this paper, we develop the criterion on the upper semi-continuity of random attractors by a weak-to-weak limit replacing the usual norm-to-norm limit. As an application,we obtain the convergence of random attractors for non-autonomous stochastic reactiondiffusion equations on unbounded domains, when the density of stochastic noises approaches zero. The weak convergence of solutions is proved by means of Alaoglu weak compactness theorem. A differentiability condition on nonlinearity is omitted, which implies that the existence conditions for random attractors are sufficient to ensure their upper semi-continuity.These results greatly strengthen the upper semi-continuity notion that has been developed in the literature. 相似文献
10.
Tongzhu LI 《数学年刊B辑(英文版)》2017,38(5):1131-1144
Let x : M~n→ S~(n+1) be an immersed hypersurface in the(n + 1)-dimensional sphere S~(n+1). If, for any points p, q ∈ Mn, there exists a Mbius transformation φ :S~(n+1)→ S~(n+1) such that φox(Mn~) = x(M~n) and φ ox(p) = x(q), then the hypersurface is called a Mbius homogeneous hypersurface. In this paper, the Mbius homogeneous hypersurfaces with three distinct principal curvatures are classified completely up to a Mbius transformation. 相似文献
11.
Pullback attractors for modified swift-hohenberg equation on unbounded domains with non-autonomous deterministic and stochastic forcing terms 下载免费PDF全文
In this paper, the existence and uniqueness of pullback attractors for the modified Swift-Hohenberg equation defined on $R^{n}$ driven by both deterministic non-autonomous forcing and additive white noise are established. We first define a continuous cocycle for the equation in $L^{2}(R^{n})$, and we prove the existence of pullback absorbing sets and the pullback asymptotic compactness of solutions when the equation with exponential growth of the external force. The long time behaviors are discussed to explain the corresponding physical phenomenon. 相似文献
12.
Regularity of pullback attractors and random equilibrium for non-autonomous stochastic FitzHugh-Nagumo system on unbounded domains 下载免费PDF全文
This paper is concerned with the stochastic Fitzhugh-Nagumo system with non-autonomous terms as well as Wiener type multiplicative noises. By using the so-called notions of uniform absorption and uniformly pullback asymptotic compactness, the existences and upper semi-continuity of pullback attractors are proved for the generated random cocycle in $L^l(\mathbb{R}^N)\times L^2(\mathbb{R}^N)$ for any $l\in(2,p]$. The asymptotic compactness of the first component of the system in $L^p(\mathbb{R}^N)$ is proved by a new asymptotic a priori estimate technique, by which the plus or minus sign of the nonlinearity at large values is not required. Moreover, the condition on the existence of the unique random fixed point is obtained, in which case the influence of physical parameters on the attractors is analysed. 相似文献
13.
本文证明了不可约的$L(A)$-模是$A$-模的充要条件,给出了单的$n+1$-维$n$-李代数的有限维不可约表示的分类. 相似文献
14.
研究了$(n+p)$维双曲空间$\mathbb{H}^{n+p}$中完备非紧子流形的第一特征值的上界.特别地,证明了$\mathbb{H}^{n+p}$中具有平行平均曲率向量$H$和无迹第二基本形式有限$L^q(q\geq n)$范数的完备子流形的第一特征值不超过$\frac{(n-1)^2(1-|H|^2)}{4}$,和$\mathbb{H}^{n+1}(n\leq5)$中具有常平均曲率向量$H$和无迹第二基本形式有限$L^q(2(1-\sqrt{\frac{2}{n}})
相似文献
15.
THE DIRICHLET PROBLEM FOR DIFFUSION EQUATION 总被引:2,自引:0,他引:2
Let D be a bounded domain in the d 1-dimensional Euclidean space R~(d 1). This paper aims at giving a probabilistis treatment of the Dirichlet problem for the following diffusion equation on D(1/2⊿ q)u(x,t)=/(t)u(x,t),(x,t)∈D,where q is a function to be specified later and ⊿ is the Laplace operator sum from i=1 to d(~2/(x_i~2)). The existence and uniqueness theorems are given, and furthermore, the probabilistie representation and martingale charaeterization of the solutions for diffusion equations are obtained. 相似文献
16.
Let $M^{n}(n\geq4)$ be an oriented compact submanifold with parallel
mean curvature in an $(n+p)$-dimensional complete simply connected
Riemannian manifold $N^{n+p}$. Then there exists a constant
$\delta(n,p)\in(0,1)$ such that if the sectional curvature of $N$
satisfies $\ov{K}_{N}\in[\delta(n,p), 1]$, and if $M$ has a lower
bound for Ricci curvature and an upper bound for scalar curvature,
then $N$ is isometric to $S^{n+p}$. Moreover, $M$ is either a
totally umbilic sphere $S^n\big(\frac{1}{\sqrt{1+H^2}}\big)$, a
Clifford hypersurface
$S^{m}\big(\frac{1}{\sqrt{2(1+H^2)}}\big)\times
S^{m}\big(\frac{1}{\sqrt{2(1+H^2)}}\big)$ in the totally umbilic
sphere $S^{n+1}\big(\frac{1}{\sqrt{1+H^2}}\big)$ with $n=2m$, or
$\mathbb{C}P^{2}\big(\frac{4}{3}(1+H^2)\big)$ in
$S^7\big(\frac{1}{\sqrt{1+H^2}}\big)$. This is a generalization of
Ejiri''s rigidity theorem. 相似文献
17.
18.
X. G. Lu 《计算数学(英文版)》1997,15(1):81-96
1,Iotroduction.InthispaPerwe8tudytherepresentationofDaubechies'wavelets.DaubechiesI1]constructedaf4milyofcompartlysupportedregularscallngfUnctionsrk.(x)andtheassoci4tedregularwpeletsop.(x)(N32):where4.eL'(R)definedbythep0lyn0mia:withZq.(k)=1'q.(k)ER,k=0,1,')N-1.Itisknownthat[1]f0reachN32,k=Osuppgh.=[0,2N-l],suppop.=[-(N-1),N]andthewaveletop.generatesbyitsdilatiOnsandtranslati0nsan0rth0rn0rmalbasis{m.(2ix-k)}i,k6Z0fL'(R).Thefunctionsrk.andop.havebeenprovedtobeveryusefulinnumericalanal… 相似文献
19.
Ronald L. Graham Jeffrey C. Lagarias Colin L. Mallows Allan R. Wilks Catherine H. Yan 《Discrete and Computational Geometry》2006,35(1):37-72
This paper gives $n$-dimensional analogues of the Apollonian circle packings in Parts I and II. Those papers considered circle
packings described in terms of their Descartes configurations, which are sets of four mutually touching circles. They studied
packings that had integrality properties in terms of the curvatures and centers of the circles. Here we consider collections
of $n$-dimensional Descartes configurations, which consist of $n+2$ mutually touching spheres. We work in the space $M_D^n$
of all $n$-dimensional oriented Descartes configurations parametrized in a coordinate system, augmented curvature-center coordinates,
as those $(n+2) \times (n+2)$ real matrices $W$ with $W^T Q_{D,n} W = Q_{W,n}$ where $Q_{D,n} = x_1^2 + \cdots + x_{n+2}^2
- ({1}/{n})(x_1 +\cdots +
x_{n+2})^2$ is the $n$-dimensional Descartes quadratic form, $Q_{W,n} = -8x_1x_2 + 2x_3^2 + \cdots + 2x_{n+2}^2$, and $\bQ_{D,n}$
and $\bQ_{W,n}$ are their corresponding symmetric matrices. On the parameter space $M_D^n$
of augmented curvature-center matrices, the group ${\it Aut}(Q_{D,n})$ acts on the left and ${\it Aut}(Q_{W,n})$ acts on
the right. Both these groups are isomorphic to the $(n+2)$-dimensional Lorentz group $O(n+1,1)$, and give two
different "geometric" actions. The right action of ${\it Aut}(Q_{W,n})$
(essentially) corresponds to Mobius transformations acting on the underlying
Euclidean space $\rr^n$ while the left action of ${\it Aut}(Q_{D,n})$ is
defined only on the parameter space $M_D^n$. We introduce $n$-dimensional analogues of the Apollonian group, the dual Apollonian
group and the super-Apollonian group. These are finitely generated groups in ${\it Aut}(Q_{D,n})$, with
the following integrality properties: the dual Apollonian group consists of integral matrices in all dimensions, while the
other two consist of rational matrices, with denominators having prime divisors drawn from a finite set $S$ depending on the
dimension. We show that the Apollonian group and the dual Apollonian group are finitely presented, and are Coxeter groups.
We define an Apollonian cluster ensemble to be any orbit under the Apollonian group, with similar notions for the other two
groups. We determine in which dimensions there exist rational Apollonian cluster ensembles (all curvatures are rational) and
strongly rational Apollonian sphere ensembles (all augmented curvature-center coordinates are rational). 相似文献
20.
We introduce a notion of mild solution for a class of non-autonomous parabolic stochastic partial differential equations defined on a bounded open subset ${D\subset\mathbb{R}^{d}}We introduce a notion of mild solution for a class of non-autonomous parabolic stochastic partial differential equations defined
on a bounded open subset and driven by an infinite-dimensional fractional noise. We prove the existence of such a solution, establish its relation
with the variational solution introduced by Nualart and Vuillermot (J Funct Anal 232:390–454, 2006) and the H?lder continuity
of its sample paths when we consider it as an L
2(D)-valued stochastic process. When h is an affine function, we also prove uniqueness. An immediate consequence of our results is the indistinguishability of mild
and variational solutions in the case of uniqueness.
M. Sanz-Solé was supported by the grant MTM 2006-01351 from the Dirección General de Investigación, Ministerio de Educación
y Ciencia, Spain. 相似文献