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1.
Let ψ(r) is a positive function on [0, ∞),ψ(r)∞(r→∞), andLet φ is such function family that if φ(z)∈φ, then φ(z) is analytic in thesemi-plane Rez>0, continuous on Rez≥0, φ(z)≠0, and  相似文献   

2.
In this paper,for any local area-minimizing closed hypersurface∑with RcΣ=RΣ/ngΣ,immersed in a(n+1)-dimension Riemannian manifold M which has positive scalar curvature and nonnegative Ricci curvature,we obtain an upper bound for the area of∑.In particular,when∑saturates the corresponding upper bound,∑is isometric to Snand M splits in a neighborhood of∑.At the end of the paper,we also give the global version of this result.  相似文献   

3.
高福根  杨长森 《数学季刊》2008,23(1):135-139
In this paper,firstty we shall show some equivalent conditions of A>B>0;secondly by using the results of ours we shall show some characterizations of the chaotic order(i.e.,log A≥log B)by norm inequalities.  相似文献   

4.
A CRACK PROBLEM WITH A BROKEN LINE INTERFACE   总被引:1,自引:0,他引:1  
§0.IntroductionConsiderableplanecrackproblemsofcompositemediaforthecaseinwhichtheinterfaceisaninfinitestraightlinewerestudied...  相似文献   

5.
Matrices and operators of the formA –1 A * have received a certain amount of attention in recent years. Here some of the literature is surveyed and the caseA –1 A is studied for complex matrices withA denoting the transpose ofA. A generalization ofA –1 A is introduced.
Zusammenfassung Matrizen und Operatoren, die in der FormA –1 A * ausgedrückt werden können, sind in den letzten Jahren häufig studiert worden. Hier wird ein Ueberblick über Teil der relevanten Literatur gegeben und auch der FallA –1 A für komplexe Matrizen studiert, wobeiA die Transponierte vonA ist. Es wird auch eine Verallgemeinerung vonA –1 A eingeführt.


Dedicated to Eduard Stiefel by a long time admirer  相似文献   

6.
A CORRECTION     
江泽涵 《数学学报》1937,2(2):341-342
<正> In my paper entitled'On the Poincaré's groups and the extendeduniversal coverings of closed orientable two-manifolds”,the conversepart of (i) of Number 7 is not valid and should be omitted.The firstplace where this conve(?)se part was used is in the proof of(iii)ofNumber 7.To make the correction,at the end of(i)of Number 5 wereplace“not reduced.”by“not reduced, but (u_(1,1)) (u_(1,2))is reduced”,and to(iii)of Number 5 we add“When u_(1,2) is not the(2p-1)st f.e.  相似文献   

7.
Asiswellknown,nonlineartwo-pointboundaryvalueproblemisaclassicalbasicproblem.Theresultsofthisproblemareusuallyratherperfect.But,somenewproofsandimprovementsoftheseresultswillbeverymeaningfulandprofittherelatedproblem.Considerthefollowingboundaryvalueproblemwhereh(t,xl,x2)andf(t,xl,x2)arecontinuous,f(t,xl)x2)isboundedfortE[0,r],--co相似文献   

8.
Smirnov  V. A. 《Mathematical Notes》2001,69(5-6):827-832
In the paper conditions are found under which the A-structure on the homology of a differential algebra degenerates. Examples of such algebras are given. In particular, it is shown that the A-algebra structure on the Milnor coalgebra degenerates, and that if the cohomology of a topological space is a polynomial algebra, then the A-algebra structure on it degenerates.  相似文献   

9.
We prove some new retarded nonlinear integral inequality and present its applications to the global existence of differential equations with delay.  相似文献   

10.
A HOPF INDEX THEOREM FOR A REAL VECTOR BUNDLE   总被引:1,自引:1,他引:0  
The authors generalize the works in [5] and [6] to prove a Hopf index theorem associated to a smooth section of a real vector bundle with non-isolated zero points.  相似文献   

11.
设A是布尔矩阵,而矩阵G满足AGA=A.(1)如果对所有Ax=y的向量x,y.有ω(Gy)≤ω(x)(*)称G是A的一个极小权g-逆,表示为A-ω.(2)如果对所有向量x,y,有d(AGy,y)≤d(Ax,y)(**)称G是A的最小距离g-逆,表示为A-d.(3)如果(*)和(**)都成立,就称G是极小权最小距离g-逆,表示为A-ωd.本文研究这三类广义逆矩阵的最大逆的存在性及表示式.主要结果如下:假定对于矩阵A.A-ω,A-d,A-ωd分别存在,那么.(1)存在最大A-ω,当且仅当A中设有两个相同的非零列,且最大A-ω为Aω=[ICAT]C.(2)最大A-d存在,且为Ad=[ATACAT+AT(JAT)C]C.(3)存在最大A-ωd,当且仅当A的所有非零列向量线性独立,且最大A-ωd为Aωd=[ATAcAT+AT(JAT)c+(ATJ)cAT]C.其中J为全1矩阵  相似文献   

12.
1.IntroductionSuperprocesses,i.e.,measure-vauedMarkovprocesses,havebeenanattractivetopicintherecenty6ars,whichcanbedefinedasfollows.Let((,Px)..MbeaMarkovprocesswithstrongcontinuousMarkovsemigroupSt(denotebyAitsinfinitesimaloperator,andbyPt(x,y)theassociatedtransitiollfunction).DenotebyMPthesetofallRadonmeasurespsatisfyingandbypC(t)(resp.pCc(t))thesetofpositivelycontinuousfUnctions(resp.withcompactsupport)int-Thesthcalledsuperprocess(X,P#).6MPwithparameters(andopandtakingvalueinMrisdete…  相似文献   

13.
In this article we obtain a nonnegative rank factorization of nonnegative matrices A satisfying one or both of the following conditions: (i) AA ? ? 0 (ii) A ? A ? 0, thus providing a new set of conditions that guarantee the existence of a nonnegative least-squares solution of a linear system. Indeed, the characterization of such matrices improves some of the previous known conditions for the existence of a nonnegative least-squares solution of a linear system.  相似文献   

14.
根据共轭相似的定义和性质对A(A-)的性质作进一步的研究,特别是A(A-)的负特征值的分布的结论,将对研究共轭特征值的分布和正规矩阵的特征值分布有重大意义.  相似文献   

15.
This note simplifies Cordoba-Fefferman's proof on the weak boundedness of strong maximal operator M_8 (with respect to dμ) on L(1+log~(+(n-1))L). Some two-weighted boundedness results on L(1+log~(+α)L) of M_8 are investigated.  相似文献   

16.
Assume that B is a compact subset on the real axis containing at least n+1 points,C(B) the normed linear space of all continuous functions defined on B,with Chebyshevnorm‖·‖,and G=span(g_1,…,g_n) an n-dimensional subspace of C(B).LetG_R={g=sum from j=1 to n a_jg_j:v(x)≤g(x)≤u(x),q_i≤sum from j=1 to n d_(ij)a_j≤p_i for i=1,…,l}where u,v are extended real-valued functions on B subject to -∞≤v(x)相似文献   

17.
The graphs considered here are finite, undirected and simple. The sets ofvertices and edges of a graph G are denoted by V(G) and E(G), respectively.A graph G is called to be numbered if each vertex υ of G is assigned a nonnegative integer φ(υ), and each edge {u,υ} is assigned the absolute value of thedifference of the numbers at its endpoints, i.e.,|φ(u)-φ(υ)|.  相似文献   

18.
In this paper, when μ< 1/4, and 2 0 and q=2(3-σ),the method is coming from the idea of Pohozaev.  相似文献   

19.
利用方阵的Jordan分解与翻转矩阵等技巧,给出方阵A、B及其张量积AB性质间的关系.  相似文献   

20.
A BIOCHEMICAL OSCILLATION   总被引:1,自引:0,他引:1  
In this note, we consider a simplest biochemical system that with only two chemical species and two cells. Higgins (1967) suppose that species X and Y react according to the scheme:  相似文献   

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