半空间中一类推广的Poisson积分的增长性质

本文研究了推广的Poisson积分的增长性问题.利用复平面中经典的Hayman定理及其证明方法,通过修改上半空间中的Poisson积分,获得了上半空间中一类位势在无穷远点的增长性质,推广了Hayman定理在高维空间的结果.     

修改的Poisson核和调和函数的积分表示

在本文中,对于半平面中的调和函数u(z),利用半平面中修改的Poisson核,证明了如果它的正部u~ (z)=max{u(z),0}满足某些限制增长条件,则它可以用半平面边界上的积分表示出来,并且它的负部u~-(z)=max{-u(z),0}也被类似的增长条件所控制,这一结果改进了在半平面中调和函数的某些经典结果。     

锥中修改Green函数的构造及其应用

首先构造了一个锥中修改的Green函数,给出了其增长性质.作为应用,接着得到了锥中Dirichlet问题的通解.最后证明了这种解表示形式的唯一性.     

半空间中一类调和函数的例外集

利用Whitney方体的相关性质, 给出了一类调和函数在半空间中无穷远点处的增长估计, 且刻画了其 例外集的几何性质. 本文推广了张艳慧和邓冠铁在半空间中的相关结果.     

微分多项式的例外集

设ｆ为任一超越整函数，为ｆ的任一微分多项式；本文证明了在满足｜ａ＿ｎ－ａ＿ｍ｜＞ε｜ａ＿ｎ｜（ｎ≠ｍ）和的无穷个圆盘的并集之外取任意有限非零复数无穷次。     

亚纯函数导数的例外集

1 引言及结果 设f是复平面C中超越亚纯函数.亚纯函数a_i(z)称为小函数,若a_i(z)满足T(r,a_i)=o(T(r,f))(i=1,2,…)。我们采用Nevanlinna理论中常用记号,用S(r,f)表示量:当f为有穷级时S(r,f)=O(log r);当f为无穷级时S(r,f)=O(log r T(r,f)),至多除去r的一个有限测度集。     

亚纯函数的例外集

自从Ｌｅｈｔｏ Ｏ．［１］提出例外集的概念后,这方面已有不少工作,但这些工作基本上是局限于整函数来做的,主要原因是极点给证明带来很大困难．本文证明了任一个满足δ（∞,ｆ）＞３／４的超越亚纯函数ｆ（ｚ）,ｆｋＱ［ｆ］在任一不含ｆ和Ｑ［ｆ］极点的可数个圆盘并集之外取任何非零复数无穷次,其中ｋ≥１５／８＋１／２ГＱ,ГＱ是ｆ的微分多项式 Ｑ［ｆ］的权．本文的结果推广了 Ｈａｘｍａｎ等人的结论．     

平面中Poisson方程的Dirichlet问题

基于向量旋转内积不变的特点,通过对Green积分公式的推广,得到与空间Green三个公式相似的平面Green公式.从而,得到平面中Poisson方程Robin问题的解和平面中Poisson方程Dirichlet问题的解.     

上半空间中一类次调和函数的增长估计

本文证明了n-维(n≥2)Euclidean空间的上半空间中Poisson积分在无穷远点处的增长性质.同时将这个性质推广到次调和函数中去,其概括了解析函数和调和函数的增长性质.     

亚纯函数的例外集

亚纯函数的例外集问题的已有结论,还未触及例外集内含有极点的情形.本文证明了对于满足δ(∞,f)>0的超越亚纯函数f(z),设F=fk则F′的可数个圆盘并集之外取任何非零有穷复数无穷次,或者取∞无穷次,本文推广了Hayman,Andersom等人的结论.     

Poisson Kernel and Green Function of the Ball in Real Hyperbolic Spaces

Let (X _t ) _t⩾0 be the n-dimensional hyperbolic Brownian motion, that is the diffusion on the real hyperbolic space having the Laplace–Beltrami operator as its generator. The aim of the paper is to derive the formulas for the Gegenbauer transform of the Poisson kernel and the Green function of the ball for the process (X _t ) _t⩾0. Under additional hypotheses we prove integral representations for the Poisson kernel. This yields explicit formulas in and spaces for the Poisson kernel and the Green function as well.      

Growth estimates for modified Green potentials in the upper-half space

In this paper, we construct a modified Green potential in the upper-half space of the n-dimensional Euclidean space. Meanwhile, the behavior at infinity of it is also given.     

The modified Green function technique for the exterior Dirichlet problem in linear thermoelasticity

In this work, the modified Green function technique for the exterior Dirichlet problem in linear thermoelasticity is presented. Expressing the solution of the problem as a double‐layer potential of an unknown density, we form the associated boundary integral equation that describes the problem. Exploiting that the discrete spectrum of the irregular values of the associated integral equation is identified with the spectrum of eigenvalues of the corresponding interior homogeneous Neumann problem for the transverse part of the elastic displacement field, we introduce a modification of the fundamental solution of the elastic field. We establish the sufficient conditions that the coefficients of the modification must satisfy to overcome the problem of nonuniqueness for the thermoelastic problem.     

Comparison of Green Functions and Harmonic Measures for Parabolic Operators

In this paper, we prove two-sided pointwise estimates for the Green function of a parabolic operator with singular first order term on a C^1,1-cylindrical domain . Basing on these estimates, we establish the equivalence of the parabolic measure, the adjoint parabolic measure and the surface measure on the lateral boundary of . These results are first studied by some authors for certain elliptic and less general parabolic operators. Mathematics Subject Classifications (2000) 31B25, 35B05, 35K10, 58J35.     

On the Size of the Exceptional Set in Nevanlinna's Second Fundamental Theorem for Certain Classes of Meromorphic Functions

Some conditions on the size of the exceptional set that arise in Nevanlinna's Second Fundamental Theorem are established, showing that previous sharp results can be improved by restricting the class of functions considered and suggesting a close relationship between the size of the exceptional set and the lower growth of the characteristic function. Examples of functions of rapid growth possessing exceptional sets are built, showing that these conditions are sharp for the class of functions considered.     

Non-singular Green’s functions for the unbounded Poisson equation in one,two and three dimensions

In this paper, we derive the non-singular Green’s functions for the unbounded Poisson equation in one, two and three dimensions using a spectral cut-off function approach to impose a minimum length scale in the homogeneous solution. The resulting non-singular Green’s functions are relevant to applications which are restricted to a minimum resolved length scale (e.g. a mesh size $h$) and thus cannot handle the singular Green’s function of the continuous Poisson equation. We furthermore derive the gradient vector of the non-singular Green’s function, as this is useful in applications where the Poisson equation represents potential functions of a vector field.     

Description of Simple Exceptional Sets in the Unit Ball

For z B ⁿ, the boundary of the unit ball in . If the exceptional set for f. In this note we give a tool for describing such sets. Moreover we prove that if Eis a G and F subset of the projective (n– 1)-dimensional space then there exists a holomorphic function fin the unit ball B ⁿso that E(f) = E.     

Green functions and related boundary value problems on the Heisenberg group

In this article, a modified Kelvin transform on ? _n using inversion with respect to a ball of arbitrary radius is defined, which gives explicit expressions for Green's function and Poisson's kernel for the Korányi ball of arbitrary radius and annular domain. The solution of the Dirichlet problem for the union of two balls is discussed using the Schwarz's alternating method.     

Calculation and estimation of the Poisson kernel

We provide a simple method for obtaining boundary asymptotics of the Poisson kernel on a domain in RN.