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1.
陈清华 《数学研究》1995,28(4):46-48
本文推广CNastasecu,F.VanOystaeyen的有关结果,并在一定条件下回答了K.R.Fuller等人的公开问题.  相似文献   

2.
N.J. Groenewald 《代数通讯》2013,41(17):1681-1691
In [2] Coleman and Enochs obtained results about the units of the polynomial ring R[x] for rings R satisfying a condi-tion which is, in some sense, a generalization of commutativity. In [3] some of these results were extended to group rings over an ordered group. In this note a class of rings larger than the class considered in [2] is used to extend the results in [2] and 3] to the semigroup ring RG, G an u.p, semigroup.

In the last section we give a necessary and sufficient condi-tion for an element to be a divisor of zero in RG where G is an u.p. semigroup.  相似文献   

3.
胡文杰  逄勃 《数学研究》2000,33(1):101-104
「2」指出了「1」的某些错误,并给出了修正的结果。本继续「2」的讨论,给出了M-矩阵等价表征的进一步结果。  相似文献   

4.
NOD随机变量阵列加权乘积和的强极限定理   总被引:1,自引:0,他引:1  
本文研究了行为NOD随机变量阵列加权乘积和的完全收敛性和强稳定性,推广和改进了文献[1]和[2]在NA情形时的结果以及[4]在独立同分布情形时的结果.  相似文献   

5.
B值随机元和的完全收敛性   总被引:1,自引:0,他引:1  
在B值随机元随机有界于一非负随机变量的情况下.讨论了B值独立随机元序列非随机足标和的完全收敛性,作为应用,得到了随机足标和完全收敛性的相应结果,将[5]中的一些结果推广到B值独立随机无情形,同时使[3](d=1),[4],[6]的相应结果成为特例.  相似文献   

6.
詹小平  蔡海涛 《数学学报》2003,46(2):237-244
文[4]对简单形式的微分多项式fkf’+a的零点分布进行了讨论,文[1]对一般形式的微分多项式fkQ[f]+P[f]的零点分布进行了讨论.但由于极点给证明带来的困难,这些工作主要是对整函数来做的.本文证明了任一满足δ(∞,f)>k+2ΓQ+3ΓP+2/2k+2ΓQ+1的超越亚纯函数f,微分多项式fkQ[f]+P[f]在不含f,Q[f]极点和P[f]零、极点的可数个圆盘并集之外有无穷多个零点,其中k≥3Γp+2,而ΓQ,ΓP分别是f的微分多项式Q[f],P[f]的权.文[1]和[2,4,6]中的结论是本文结论的特殊情况.  相似文献   

7.
In this note it will be shown how a theorem of Alexander [1] and Ize [9] together with computational results of Alexander and Yorke [4] and Alexander and Fitzpatrick [2] may be used to generalize the existence theorem for, and to prove some global results about, certain wave-like solutions of nonlinear systems of partial differential equations.The equations to be studied are weakly coupled parabolic systems of equations defined on a bounded axisymmetric domain. Such equations are often called reaction-diffusion equations (or interaction-diffusion equations) and arise in many parts of biology and chemistry. The question as to how wave-like solutions of these equations may bifurcate from a family of trivial solutions was studied by Auchmuty [5] and the results will be considerably extended here.  相似文献   

8.
陈贻源[1]和张文修[2]分别引入了Fuzzy弱自反关系的定义和有关的证明。本文在[1]和[2]给出Fuzzy弱自反关系定义的基础上,对[1]和[2]的有关Fuzzy弱自反关系证明提出了异议,并给出了新的证明。  相似文献   

9.
M—矩阵的等价表征   总被引:15,自引:0,他引:15  
本文引进了按环路弱不约非零元素对角占优的概念,讨论了M-矩阵的等价条件,给出了M-矩阵的两个等价表征,改进与推广了(1),(2),(5),(9)的相应结果。  相似文献   

10.
In this letter, we show that the main results of the reply paper [1] are wrong. We demonstrate that the authors of Delavari et al. (2012) [1] have carried out an essential flaw in the proof approach of the system stability. Therefore, we prove that the defects of the paper [2] which have been described in the comment paper [3] are still continued. In this regard, we conclude that the results of our comment paper [3] are correct.  相似文献   

11.
In this paper, we consider an one-phase quasilinear Stefan-Signorini problem. In [1] X. Liu has proved the existence and the uniqueness of this problem by the traditional penalty method (see [3] and [4]). Here we use the Mixed Scheme in [2] which is more suitable to the Stefan-Signorini problem and obtain more natural existence results.  相似文献   

12.
随机不动点定理在随机泛函分析中是一重要问题.在可分完备的度量空间中的随机不动点定理Bharucha-Reid,王梓坤,?pa?ek,Han?,Itoh及作者等都曾进行过讨论(见[1-5,15-20,21]).在本文中我们对概率分析中可交换映象的随机不动点定理得出了几个新的结果,它推广了前述诸人工作中某些重要结果.在确定性情形也推广了Jungck[6,7,8],Das,Naik[9],Rhoades[10],及Ciric[11]的结果.  相似文献   

13.
石钟慈  许学军 《计算数学》1999,21(4):507-512
1.引言设 是Rd(d=2;3)中的有界多角形区域,α是它的边界.考虑下列模型问题此处f∈EL2(Ω),系数AE(C1(Ω))d×d满足下列一致椭园条件此处α0是正常数.此外假设B∈(C1(Ω)d和c∈C0(Ω)([14]).(1.1)式的变分形式是:找u∈H0(Ω)使得最近,非对称不定问题的非协调多重网格法吸引了众多的研究,详见问,[7];[10].考虑非协调元多重网格的一个重要原因是混合元和非协调元之间存在着紧密的联系(详见【几问,问).设FI是fi拟一致的H角形或矩形剖分,是由连接F'-'(…  相似文献   

14.
Using a weaker version of the Newton-Kantorovich theorem [6] given by us in [3], we show how to refine the results given in [8] dealing with the analyzing of the effect of small perturbations in problem data on the solution. The new results are obtained under weaker hypotheses and the same computational cost as in [8].  相似文献   

15.
赵家兵 《应用数学》1993,6(4):381-386
利用Kuratowski非紧致测度及[5]中有关结果,本文证明了Banach空间拟非线性发展方程B解的存在性,并且讨论了B解的一些性质。例子表明[5]及[2]的结论为本文结果之推论。  相似文献   

16.
B值随机元阵列的完全收敛性及大数定律   总被引:6,自引:1,他引:5  
该文在随机元阵列随机有界于某非负随机变量的条件下,得到了B值随机元阵列完全收敛性的一般性结论,并讨论了随机元阵列加权和的收敛性,使[5][6]中的结果得到了改进和推广.同时讨论了完全收敛性与Banach空间p型(1<P≤2)性质的等价性,使[14],[15]中的结果得到进一步的改进.  相似文献   

17.
We prove the existence of a pseudo-equilibrium in a financial economy with incomplete markets in which the agents may have nonordered preferences. We use a fixed-point-like theorem of [5] that generalizes the results by Hirsch, Magill and Mas-Colell [18] and Husseini, Lasry and Magill [19] to encompass the framework considered by Gale and Mas-Colell ([14], [15]).  相似文献   

18.
DefinitionlLl]I,etXbeaHausdorffTopologicalspacewhichhaspartiallyorderedstructure.WesayXisasemiorderedTopologicalSpace,ifforanytwonets{x.Ir6T}and{YrlrET}inX,x,相似文献   

19.
Ingham [4] improved a previous result of Wiener [10] on nonharmonic Fourier series. Modifying his weight function we obtain optimal results improving several earlier theorems of Kahane [7], Castro and Zuazua [2] and of Jaffard, Tucsnak, and Zuazua [5]. Then we apply these results to simultaneous observability problems.  相似文献   

20.
Completing a series of works begun by Wiener [34], Paley and Wiener [28] and Ingham [9], a far-reaching generalization of Parseval"s identity was obtained by Beurling [4] for nonharmonic Fourier series whose exponents satisfy a uniform gap condition. Later this gap condition was weakened by Ullrich [33], Castro and Zuazua [5], Jaffard, Tucsnak and Zuazua [11] and then in [2] in some particular cases. In this paper we prove a general theorem which contains all previous results. Furthermore, applying a different method, we prove a variant of this theorem for nonharmonic Fourier series with vector coefficients. This result, partly motivated by control-theoretical applications, extends several earlier results obtained in [15] and [2]. Finally, applying these results we obtain an optimal simultaneous observability theorem concerning a system of vibrating strings. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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