具有较一般分支特征的超布朗运动轨道性质

本文研究具有较一般分支特征的超布朗运动｛Ｘ（ｔ）｝ｔ０的轨道性质．首先给出了它的一个击中概率的表达式，其次找到了它的支集蔓延速度的估计式及证明了支撑过程的右连续性，从而验证了Ｄａｗｓｏｎ，Ｄ．Ａ．等人的猜想     

具有绝对连续测度状态的超布朗运动

设X={Xt,Pu}是d维超布朗运动,具有分支率函数A与一般分支机制ψ.讨论A满足什么条件时可以保证Xt具有绝对连续状态.特别当ψ(s,z,z)=z.时,Dawson与Fkischmann[2]讨论了类似问题.本文对他们的讨论进行了改进,将他们的结果推广到了ψ一般的情形,并且简化了他们对A所加的条件.     

具有绝对连续测度状态的超布朗运动

设X={Xt,Pμ}是d维超布朗运动,具有分支率函数A与一般分支机制ψ.讨论A满足什么条件时可以保证Xt具有绝对连续状态.特别当ψ（s,x,z）=z2时,Dawson与Fleischmann[2]讨论了类似问题.本文对他们的讨论进行了改进,将他们的结果推广到了ψ一般的情形,并且简化了他们对A所加的条件.     

超布朗运动在临近灭绝时的行为

本文研究具有一类较广泛分支特征的超布朗运动在临近灭绝时的行为，主要得到了在临近灭绝时它的支撑的直径几乎处处收敛到零     

临界超布朗运动的渐近行为

本文证明了在一般的初始测度下，Dawson所获得的临界超布朗运动的渐 近定理并不成立，对于一般分支特征的临界的超布朗运动以及一般寝始测度，本文获得了它的渐近行为的阶的两个估计。     

超布朗运动的灭绝时的分布

本文研究了超布朗运动的局部灭绝时的概率分布,并且得到了一类发展方程的解的一个性质。     

双曲空间上超布朗运动的支撑

支撑性是超过程，作为取测度值马氏过程，所特有的性质．本文通过对双曲空间（常截面曲率为－１的单连通完备黎曼流形）Ｈｄ上超布朗运动｛Ｘｔ｝ｔ０的研究给出关于｛Ｘｔ｝ｔ０支撑的一些结果，同时也对Ｈｄ上方程ΔＭｕ－ｕ２＋＝０解的一些性质进行了讨论．     

双曲空间上超布朗运动的范围

对双曲空间上的超布朗运动进行了研究,证明了该过程的范围属于某集合的概率可以表示为一个奇异边值问题的解.在得到了这个解的一个极限结果以后,给出了上述概率的一个渐近行为.对于维数d≥2,还证明了从黎曼测度出发的超过程在任何内点非空的有界Borel子集上的占位时是无穷的结论.     

超布朗运动关于区域的首中方式

应用Ｌｅ Ｇａｌｌ的超布朗运动的轨道构造,研究超布朗运动关于区域的着中方式,证明了它在首中一个区域时,其支撑集与区域闭包的交集的点数不大于２,并提出了一个猜想。     

从超布朗运动到随机偏微分方程

随机偏微分方程(SPDE)是目前国内外广泛关注研究进展迅速的一个活跃的学术研究领域.该主题的研究涉及概率论(随机分析、随机场)、偏微分方程、调和分析等诸多分支学科方向.特别是随机偏微分方程其背景更多地源于现代物理学、化学、生物学、经济学等应用性学科,这使得该领域的研究显示出较强的意义和活力.本文从超布朗运动研究出发,发展性地提出有较强背景意义的典型类随机偏微分方程,并进而过渡到一般及更广泛类的随机偏微分方程的研究.同时我们系统地总结了关于高阶随机偏微分方程和随机波动方程的研究成果.     

Superprocesses arising from interactive stochastic flows

In this paper, we give a unified construction for superprocesses with dependent spatial motion constructed by Dawson, Li, Wang and superprocesses of stochastic flows constructed by Ma and Xiang. Furthermore, we also give some examples and rescaled limits of the new class of superprocesses.     

Pathwise Convergence of a Rescaled Super-Brownian Catalyst Reactant Process

Consider the one-dimensional catalytic super-Brownian motion X (called the reactant) in the catalytic medium which is an autonomous classical super-Brownian motion. We characterize both in terms of a martingale problem and (in dimension one) as solution of a certain stochastic partial differential equation. The focus of this paper is for dimension one the analysis of the longtime behavior via a mass-time-space rescaling. When scaling time by a factor of K, space is scaled by K ^η and mass by K ^−η. We show that for every parameter value η ≥ 0 the rescaled processes converge as K→ ∞ in path space. While the catalyst’s limiting process exhibits a phase transition at η = 1, the reactant’s limit is always the same degenerate process.      

Functional Central Limit Theorem for the Super-Brownian Motion with Super-Brownian Immigration

The functional central limit theorems are proved for super-Brownian motion with immigration and their occupation time processes. For the lower dimensions, the limiting processes are Gaussian processes; For the critical dimension, the limiting processes consist of two ingredient processes of different types. Interestingly, for the higher dimensions, the limiting process for the occupation time process is of a new type.     

双曲空间上超布朗运动的范围

对双曲空间上的超布朗运动进行了研究,证明了该过程的范围属于某集合的概率可以表示为一个奇异边值问题的解．在得到了这个解的一个极限结果以后,给出了上述概率的一个渐近行为．对于维数d≥2,还证明了从黎曼测度出发的超过程在任何内点非空的有界Borel子集上的占位时是无穷的结论．     

A Continuous Super-Brownian Motion in a Super-Brownian Medium

A continuous super-Brownian motion is constructed in which branching occurs only in the presence of catalysts which evolve themselves as a continuous super-Brownian motion . More precisely, the collision local time (in the sense of Barlow et al. ⁽¹⁾) of an underlying Brownian motion path W with the catalytic mass process goerns the branching (in the sense of Dynkin's additive functional approach). In the one-dimensional case, a new type of limit behavior is encountered: The total mass process converges to a limit without loss of expectation mass (persistence) and with a nonzero limiting variance, whereas starting with a Lebesgue measure , stochastic convergence to occurs.     

Super-Brownian motion with reflecting historical paths. II. Convergence of approximations

We prove that the sequence of finite reflecting branching Brownian motion forests defined by Burdzy and Le Gall ([1]) converges in probability to the “super-Brownian motion with reflecting historical paths.” This solves an open problem posed in [1], where only tightness was proved for the sequence of approximations. Several results on path behavior were proved in [1] for all subsequential limits–they obviously hold for the unique limit found in the present paper.Mathematics Subject Classification (2000): Primary 60H15, Secondary 35R60Supported in part by NSF Grant DMS-0071486, Israel Science Foundation Grants 12/98 and 116/01 - 10.0, and the U.S.-Israel Binational Science Foundation (grant No. 2000065).     

关于布朗运动的一个注记

本文对布朗运动的一个充要条件给出另一种证明     

GENERALIZED BROWNIAN SHEET IMAGES AND BESSEL-RIESZ CAPACITY

Let W be a two-parameter, Rd-valued generalized Brownian sheet. The author obtains an explicit Bessel-Riesz capacity estimate for the images of a two-dimensional set under W. He also presents the connections between the Lebesgue measure of the image of W and Bessel-Riesz capacity. His conclusions also solve a problem proposed by J.-P.Kahane.     

Brownian Representations of Cylindrical Local Martingales,Martingale Problem and Strong Markov Property of Weak Solutions of SPDEs in Banach Spaces

The paper deals with three issues. First we show a sufficient condition for a cylindrical local martingale to be a stochastic integral with respect to a cylindrical Wiener process. Secondly, we state an infinite dimensional version of the martingale problem of Stroock and Varadhan, and finally we apply the results to show that a weak existence plus uniqueness in law for deterministic initial conditions for an abstract stochastic evolution equation in a Banach space implies the strong Markov property.     

Weak convergence to the fractional Brownian sheet using martingale differences

We establish an invariance principle for the fractional Brownian sheet, starting from discrete random fields constructed from two-parameter strong martingales. This is an approximation in law of the fractional Brownian sheet in Skorohord space in the plane.