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1.
有穷正级亚纯函数的T方向和Borel方向   总被引:6,自引:0,他引:6  
张庆德 《数学学报》2007,50(2):413-420
对任意正数λ,正整数q_1和q_2,记E_1={argz=θ_j|0∣θ_1<θ_2<…<θ_(q1)<2π}及E_2={axgz=φ_j|0■1<φ2<…<φq2<2π},使得E_1∩E_2=■,则(1)存在复平面上的λ级亚纯函数f(z),恰以E_1∪E_2为其T方向且恰以E_2为其Borel方向,(2)存在复平面上的级与下级均为λ的亚纯函数g(z),恰以E_1∪E_2为其Borel方向且恰以E_2为其T方向.  相似文献   

2.
设(G_1,E_1),(G_2,E_2)为两个拟格序群,记■~(E_1),■~(E_2)为相应的Toeplitz算子代数.设■:G_1→G_2为一个保单位的群同态,使得■(E_1)■E_2.本文给出了上述两个Toeplitz算子代数间的自然同态映照成为C~*-代数的单同态的充要条件,刻画了Toeplitz算子代数的归纳极限,证明了任何自由群上的Toeplitz算子代数是顺从的.  相似文献   

3.
(m)→(m)的等距算子与ε-等距算子的关系   总被引:1,自引:0,他引:1  
定义 设E_1,E_2为Banach空间,U∈B(E_1,E_2)称为等距算子是指,对x∈E_1有||Ux||=||x||;T属于B(E_1,E_2)称为ε-等距算子,是指存在0<ε<1,有(1-ε)||x||≤||Tx||≤(1 ε)||x||,x∈E_1. 本文证明了对于(m)→(m)的ε-等距算子T,其中0<ε<1/3,及任意的ε_1>0,均存在  相似文献   

4.
关于马氏场,近一二十年来,不少作者进行过研究,但多是格子点上的马氏场,例如,可参见[3]、[4]、[5]、[6]。本文作者曾在[7]中提出过度量空间上的马氏场的模型。而本文则企图把[2]中的马氏过程的模型加以拓广,研究一类所谓“各向同性的”马氏场。如不特别声明,本文符号系统沿用[2]及[7]。例如,若 E_1、E_2为二集合,由 E_1到E_2的变换 f 记作“f:E_1→E_2”,若 A(?)E_2,f~(-1)(A)定义为{x|x∈E_1,f(x)∈A},  相似文献   

5.
在分离局部凸空间中考虑free disposal集的对偶性质,其中free disposal集是指与凸锥的代数和仍是其本身的集合.在E_1或E_2是free disposal集的条件下,证明了(E_1∩E_2)~+=E_1~++E_2~+和E_1~+∩E_2~+=(E_1+E_2)~+等对偶结果.  相似文献   

6.
首先利用python3.5对铁路客座率原始数据进行预处理,然后利用ARIMA时间序列和BP神经网络进行单一的模型预测,得出单一预测模型的均方误差.在组合预测求解时,先求出ARIMA时间序列模型的误差向量E_1和BP神经网络的预测误差为E_2,由于这两种预测方法是相互独立的,因此误差向量E_1和E_2线性无关且组合预测误差向量为E=(E_1,E_2),得出组合预测平方和的形式为J-W~TEW,然后根据组合预测误差平方和最小的原则来确定权值w_1,w_2,最后求解凸二次规划问题得到权值并求出组合预测模型和均方误差.通过比较单一模型预测和组合预测的均方误差,得出结论:组合预测模型的精确度高于单一预测模型的精确度.  相似文献   

7.
孫永生 《数学学报》1962,12(3):301-319
<正> 給定Banach空間E_1,E_2及E_2的子空間A是E_2到E_1的一个綫性算子.令X_n={x_1,…,x_n}表E_1中的n个线性无关元.用記号:R={x|x∈E_1,x=Aφ,φ∈,‖φ‖2≤1}.称下面的数  相似文献   

8.
(E_1)收敛性概念首见于[1]、[2].[3],[4],[5],[6]等就序列的(E_1)收敛问题做了不少工作。本文进而引入(E_1)拓扑的概念如下: 设E是Banach空间,(E_1)是非零Banach空间,B(E,E_1)表示从E到E_1的有界线性算子全体。对任意T_1,…T_(  相似文献   

9.
关于诱导极限有界集的一些结果   总被引:2,自引:1,他引:1  
丘京辉 《数学学报》1986,29(2):280-284
<正> 设E_1■ E_2■ E_3…为局部凸Hausdorss线性拓扑空间序列,E_n所具有的拓扑记作ξ_n,(E,ξ)=indlim(E_n,ξ_n)为其相对于连续恒同映照id:(E_n,ξ_n)→(E_(n+1),ξ_(n+1))的Hausdorff诱导极限(见[1],p.57).显然,(E_n,ξ_n)的每个有界子集必为(E,ξ)的有界子集.Dieudonne-Schwartz定理指出:若对于n∈N,E_n闭于(E_(n+1),ξ_(n+1)),且ξ_(n+1)关于E_n的相对拓扑等于ξ_n,则E的子集B为ξ-有界,当且仅当存在n∈N使B为(E_n,  相似文献   

10.
关于亚纯函数族■的唯一性   总被引:2,自引:0,他引:2  
§1.引言设f(z)是开平面内非常数的亚纯函数,α为复数,λ为正整数,我们用E(α,f)表示f(z)-α的0点集合,用E_(?)(α,f)表示f(z)-α的重级不高于λ的0点集合,在上述集合中,每个0点仅计一次。有时我们也把E(α,f),E_(λ))(α,f)及E(b,f~~(k)),E_λ(b,f~(k))分别简记为E(α),E_(λ))(α)及E~((k))(b),E_(λ))~((k))(b),其中b为复数,k为正整数。在本文中,我们设F表示满足条件δ(0)=δ(∞)=1的开平面内非常数亚纯函数族。显然F中的函数均为超越亚纯函数(?  相似文献   

11.
Let Tn be the semigroup of all transformations of a set of n elements and k a field of characteristic 0. According to Ponizovskii, the semigroup algebra kTn is of finite representation type if n h 3. According to Putcha, kTn is of infinite representation type if n S 5. Here, we deal with the remaining case n=4 and show that kT4 is also of finite representation type. Note that the quiver of kT4 already has been exhibited by Putcha, here we determine the relations. It turns out that kT4 is a string algebra and its global dimension is 3.  相似文献   

12.
Y. Chen 《Semigroup Forum》2001,62(1):41-52
. Let A be a nonempty subset of an associative ring R . Call the subring CR(A)={r] R\mid ra=ar \quadfor all\quad a] A} of R the centralizer of A in R . Let S be a semigroup. Then the subsemigroup S'= {s] S\mid sa=sb \quador\quad as=bs \quadimplies\quad a=b \quadfor all a,b] S} of S is called the C -subsemigroup. In this paper, the centralizer CR[S](R[M]) for the semigroup ring R[S] will be described, where M is any nonempty subset of S' . An non-zero idempotent e is called the central idempotent of R[S] if e lies in the center of R[S] . Assume that S\backslash S' is a commutative ideal of S and Annl(R)=0 . Then we show that the supporting subsemigroup of any central idempotent of R[S] must be finite.  相似文献   

13.
Let S be an inverse semigroup and rho an idempotent separating congruence on S. It is proved that S can be embedded into a lambda-semidirect product of a group F by S/rho where F belongs to the variety generated by the idempotent classes of rho.  相似文献   

14.
The Semigroup of Hall Matrices over Distributive Lattices   总被引:3,自引:0,他引:3  
Yijia Tan 《Semigroup Forum》2000,61(2):303-314
In this paper, the semigroup Hn(L) of Hall matrices over a complete and completely distributive lattice L is studied. A Hall matrix is a matrix which is greater (for the order associated with the lattice structure) than an invertible matrix. Some necessary and sufficient conditions for a Hall matrix to be regular in the semigroup Hn(L) are given and Green's relations of the semigroup Hn(L) are described. Also, the sandwich semigroup of Hall matrices over the lattice L is studied.  相似文献   

15.
The topological interpretations of some of the algebraic properties of the semigroup Sn of singular endomorphisms of an n-dimensional vector space over K are discussed here. Since Sn is known to be an idempotent generated regular semigroup, we pay more attention to the topological properties of the set En of idempotents in Sn. The local structure of En is shown to be that of a Cinfinity-manifold and of a finite-dimensional vector bundle over the Grassmann manifolds. The topology of the biorder relations and sandwich sets are also discussed.  相似文献   

16.
For a left type-A monoid S, let tau be the congruence on S generated by R*. There exists a congruence rho on S which induces the least right cancellative congruence on each of the tau-classes. In this paper we investigate the congruence rho and give a structure theorem for the class of all left-type-A monoids for which rho intersection R* is the identity relation.  相似文献   

17.
In this paper we prove that if E is the strict inductive limit of a sequence of Mackey spaces {En} such that for every positive integer n, the topological dual space of En, E′n, provided with the Mackey topology μ(E′n,En), is ultrabornological, then the topological dual space E′ of E, provided with the Mackey topology μ(E′,E), is ultrabornological. We also prove that if E is a strict (LF)-space and G a closed subspace of E′ [μ(E′,E)] such that E′[μ(E′,E)] /G is sequentially complete, then E′[μ(E′,E)]/G is complete.  相似文献   

18.
K. Geetha 《Semigroup Forum》1999,58(2):207-221
Let V be a vector space of dimension n over a field K. Here we denote by Sn the set of all singular endomorphisms of V. Erdos [5], Dawlings [4] and Thomas J. Laffey [6] have shown that Sn is an idempotent generated regular semigroup. In this paper we apply the theory of inductive groupoids, in particular the construction of the idempotent generated regular semigroup given in §6 of [8] to detemine some combinatorial properties of the semigroup Sn.  相似文献   

19.
A finite semigroup S is said to be efficient if it can be defined by a presentation (A | R) with |R| -|A|=rank(H2(S)). In this paper we demonstrate certain infinite classes of both efficient and inefficient semigroups. Thus, finite abelian groups, dihedral groups D2n with n even, and finite rectangular bands are efficient semigroups. By way of contrast we show that finite zero semigroups and free semilattices are never efficient. These results are compared with some well-known results on the efficiency of groups.  相似文献   

20.
In the infinite dimensional case it is known from a Dineen-Nachbin counterexample that the natural generalization of the Paley-Wiener-Schwartz theorem is no longer valid: The image through the Fourier transform F of the space ?′(E) is made of entire functions on E′ that, besides the usual inequality, satisfy a more technical condition. We define and study here a dense subspace, denoted by E(E), of ?(E) with a proper topology such that F (E′(E)) is made of the entire functions on E′ that satisfy only the classical inequality. For this reason this space E(E) is suited for the study of convolution and partial differential equations in spaces of C functions on locally convex spaces.  相似文献   

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