首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 718 毫秒
1.
吴奖伦 《数学学报》1995,38(4):490-497
本文证明:若强对偶多重Hibert空间上的(C0,1)-半群族的无穷小生成算子族是Г-稳定的,则该半群族生成Г-稳定的发展系。基于此,本文还得出了关于(C0,1)-发展系的一个摄动定理。  相似文献   

2.
姚景齐 《数学学报》1997,40(5):665-668
在空间Lp(Rn),1≤p<∞中,Poison算子半群e--△z是右半平面Rez>0上的解析半群.本文考虑它的边界值,证明了闭稠定算子-i-△对某个α≥0生成了一个指数有界(I+-△)-α 半群.  相似文献   

3.
本文首次引入算子集合的C_σ性质和性质的概念,它们与性质C和性质D_σ(1)有一定的关系.两个主要结果是:(1)具有性质C_σ的对偶代数一定是遗传自反的.(2)如果对偶代数所生成的n-自反代数具有性质C_σ,则该对偶代数一定是遗传n-自反的.  相似文献   

4.
纪培胜 《数学学报》1996,39(4):477-482
设Gi是满足第二可数性公理的、Hausdorff的、顺从的、r-离散的、主的局部紧群胚,并且有一个紧开G-集覆盖;设Pi是Gi中含G_i ̄0的开闭集,且满足及相应的模是具有性质DC的C(Gi)的子代数(i=1,2).本文证明从A(P1)到A(P2)上的每一个等距代数同构可以扩张成从C(G1)到C(G2)上的C-同构,进一步,可以对C(G2)重新坐标化,使得这个C-同构可由一个群胚同构生成.  相似文献   

5.
设n≥3,记∑_(n-2)是R ̄(n-1)中的单位球面。本文研究了当Ω为R ̄(n-1)上的零次齐次函数,满足消失性条件且Ω∈时,沿某类曲面(t,г(|t|))的下列奇异积分算子Tf(x,x_n)=p.v.dt及其极大算子的L ̄p(R ̄n)-有界性,其中b为有界径向函数,x∈R ̄(n-1),x_n∈R且1<p<∞.  相似文献   

6.
对于f(z)=∑α_ne(nz)∈S_k(г_0(N)),H.Iwaniec ̄[2]证明了,其中n为无平方因子正整数.在本文中我们将推广这个结果.  相似文献   

7.
奇异半线性发展方程的局部Cauchy问题   总被引:9,自引:1,他引:8  
蹇素雯 《数学学报》1997,40(5):793-800
本文在Banach空间E中讨论如下问题dudt+1tσAu=J(u),0<tT,limt→0+u(t)=0,其中u:(0,T]E,A是与t无关的线性算子.(-A)是E上C0半群{T(t)}t0的无穷小生成元,常数σ1,J是一个非线性映射EJ→E.它满足局部Lipschitz条件.我们证明了当其Lipschitz常数l(r)满足一定条件时.问题(S)有局部解,且在某函类中解唯一.设J(u)=|u|γ-1u+f(x)(γ>1),E=Lp,EJ=Lpγ时得到了与Weisler[2]在非奇异情形类似的结果.  相似文献   

8.
陈永高 《数学学报》1994,37(1):32-42
对任给的正实数u,令C_u={(x,y,z):u ̄2x ̄2+y ̄2+z ̄2≤1}.α为一正实数,使得对于任给的射线x_i=α_it(α_i>0,i=1,2,3,t≥0)都和相交。关于C_u的光线障碍问题就是要确定K(C_u)=infα.本文对所有的实数u,确定了K(C_u)的值。  相似文献   

9.
王学理 《数学学报》1995,38(1):51-66
设r为一个正实数,1<r<2,是一个H-群,υ:Γ→C是一个乘子系(定义见文[8]).本文在[8]的基础上讨论了Poincare级数的存在性.令P_(nr)(z,υ,A_j,Γ,k_j)=P_(nr)(z,0,υ,Γ,k_j).这里P_(nr)(z,s,A_j,Γ,k_j)如文[8]中定义.我们有:定理{P_(nr)(z,υ,A_j,Γ,k_j)}n+k_K>0是群Γ的,权为r的具有乘子系υ的全纯歧点型模形式,且它们张成歧点型模形式所成的空间.应用这个结果,我们证明了一些模形式的性质并推导出一个重要的恒等式.该恒等式在半整权模形式的Fourier系数估计中有极重要的地位.  相似文献   

10.
本文给出了基于之零点的(0,1,…,m-2,m)插值的正则性的充要条件,其中为(n-1)次Laguerre多项式。同时基函数(若存在的话)的明显表达式也在文中给出。再者,还证明了,若该插值问题有无穷多个解,则其解的一般形式为f_0(x)+Cf_1(x)这里C为任意常数。  相似文献   

11.
k/N:G冗余表决系统的渐近稳定性   总被引:2,自引:0,他引:2  
分析了带有修理设备和多重致命及非致命操作故障的k/N(G)冗余表决系统的渐近稳定性.用该系统算子生成的正定C-半群证明了系统非负时间依赖解的存在唯一性.同时通过对系统算子谱点分布的分析,证明了本征值0对应的本征向量恰好是系统的静态解,并且,0是虚轴上系统算子唯一的谱点,从而证明了系统的渐近稳定性.  相似文献   

12.
苏维钢  钟怀杰 《数学学报》2007,50(4):781-788
给出一类不可分解的∑_e~1型Banach空间上线性算子(不一定有界)的谱结构,并讨论这种空间上生成C_0群或C_0半群的线性算子的有界性、特殊的谱性质和谱结构,还给出这种空间上闭算子是有界算子的一个充分条件。  相似文献   

13.
The classical theory of Sobolev towers allows for the construction of an infinite ascending chain of extrapolation spaces and an infinite descending chain of interpolation spaces associated with a given \(C_0\) -semigroup on a Banach space. In this note we first generalize the latter to the case of a strongly continuous and exponentially equicontinuous semigroup on a complete locally convex space. As a new concept—even for \(C_0\) -semigroups on Banach spaces—we then define a universal extrapolation space as the completion of the inductive limit of the ascending chain. Under mild assumptions we show that the semigroup extends to this space and that it is generated by an automorphism of the latter. Dually, we define a universal interpolation space as the projective limit of the descending chain. We show that the restriction of the initial semigroup to this space is again a semigroup and always has an automorphism as generator.  相似文献   

14.
In this paper, necessary and sufficient conditions are given for U * μ*n to converge uniformly on the real axis; here $\mu$ is a nonsingular probability measure on ℝ, and U is a Banach space valued L-function. A connection to uniform convergence of Cesaro mean values is shown. By applying the results to extended orbits of bounded C_0-semigroups on a Banach space X one can relate both kernel and range of the respective generator with those of the derivative operator on L(X). Ergodic theorems and consequences for subordinated semigroups, in particular for holomorphic semigroups, are deduced.  相似文献   

15.
Potential Analysis - We consider the stochastic differential equation dXt = A(Xt?)dZt, X0 = x, driven by cylindrical α-stable process Zt in , where α ∈ (0,1) and d...  相似文献   

16.
Lineability of sets of nowhere analytic functions   总被引:1,自引:0,他引:1  
Although the set of nowhere analytic functions on [0,1] is clearly not a linear space, we show that the family of such functions in the space of C-smooth functions contains, except for zero, a dense linear submanifold. The result is even obtained for the smaller class of functions having Pringsheim singularities everywhere. Moreover, in spite of the fact that the space of differentiable functions on [0,1] contains no closed infinite-dimensional manifold in C([0,1]), we prove that the space of real C-smooth functions on (0,1) does contain such a manifold in C((0,1)).  相似文献   

17.
《数学学报》2021,(1):I0001-I0002
Diskcyclicity of Sets of Operators and Applications Mohamed AMOUCH Otmane BENCHIHEB Abstract In this paper,we introduce and study the diskcyclicity and disk transitivity of a set of operators.We establish a diskcyclicity criterion and give the relationship between this criterion and the diskcyclicity.As applications,we study the diskcyclicty of C0-semigroups and C-regularized groups.  相似文献   

18.
This paper concerns versions of the Trotter-Kato Theorem and the Chernoff Product Formula for C 0-semigroups in the absence of stability. Applications to ${\mathcal{A}}$ -stable rational approximations of semigroups are presented.  相似文献   

19.
关于概率度量空间的等距同构   总被引:2,自引:0,他引:2  
概率度量空间理论中有两种等距同构,一种是一个概率度量空间等距同构于另一个概率度量空间.另一种是一个概率度量空间等距同于一个准度量族生成空间.该文建立了这两种等距同构之间的联系.  相似文献   

20.
In this paper, a class of evolution equations which have special boundary conditions is discussed. The spectrum properties of an operator which is associated with this class of equations arc provided, and the existence and uniqueness of solutions of this class of equations is proved by the theory of pertu rbation of C_0-semigroups. In the last part of this paper, a condition which ensures the solutions to be non-negative is given. Some results of the time-independent population systems in [1-5] are our examples.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号