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 765 毫秒
1.
In this paper, we shall present a short and simple proof on the isometric linear extension problem of into-isometries between two unit spheres of atomic abstract L^p-spaces (0 〈 p 〈 ∞).  相似文献   

2.
本文刻画了满足1/3〈λ2(G)〈(√5-1)/2的图G的结构。  相似文献   

3.
We study the extension of isometries between the unit spheres of quasi-Banach spaces Lp for 0〈p〈1. We give some sufficient conditions such that an isometric mapping from the the unit sphere of Lp(μ) into that of another LP(ν) can be extended to be a linear isometry defined on the whole space.  相似文献   

4.
Calderon—Zygmund奇异积分算子交换子的L^p有界性   总被引:1,自引:0,他引:1  
邓东皋  颜立新 《数学进展》1998,27(3):259-269
本文证明了当b∈BMO时,具有弱核的CalderonZygmund奇异积分算子交换(b,T)f=bT(f)-T(bf)是L^p(1〈p〈∞)有界的,一个等价的命题是双线性算子gT(f)-fT(g)∈H^1,只要f∈L^p,g∈L^q,1〈p〈∞,1/p+1/q=1。  相似文献   

5.
梅雪峰  周颂平 《数学进展》2005,34(6):707-716
本文失言了L[0,1]^p(1〈0〈∞)空间函数的正系数多项式的倒数逼近的结论,即证明了:设f(x)∈L[0,1]^p(1〈0〈∞),且在(0,1)内严格1次变号,则存在一点x0∈(0,1)及一个n次多项式Pn(x)∈Πn(+)使得‖f(x)-x-x0/Pn(x)‖L[0,1]^p≤Cpω(f,n^-1/2)L[0,1]^p其中Πn(+)为次数不超过n的正系数多项式的全体.  相似文献   

6.
Let L^p(Ω, H^n) indicate the L^P-space of the maps for Heisenberg group target. In this paper some new properties are obtained for the space L^p(Ω, H^n)  相似文献   

7.
Jian Yong  WANG 《数学学报(英文版)》2009,25(10):1729-1740
For 0 〈β 〈 1, the author once wrote a paper to deal with the representation problem of the conjugate cone [L^β[0, 1]β^* of complex β-nanach space L^β[0, 1]. In this paper, replacing [0, 1] with a Borel finite measure space (Ω,M,μ) and replacing the complex field C with a Banach space X, we study the representation problem of the conjugate cone [L^β(μ, X)]β^* of L^β(μ, X), and obtain [L^β(μ, X)]β^*≌L^∞ M^+(μ, S), called the Quasi-Representation Theorem of [L^β(μ, X)]β^*.  相似文献   

8.
黄克军 《数学通讯》2009,(11):15-15
题目1(2009江西卷理)设函数f(s)=√ax2+bx+c(a〈0)的定义域为D,若所有点(s,f(t))(s,t∈D)构成一个正方形区域,则a的值为( )  相似文献   

9.
在三角中有一个重要的不等式:当x∈(0,π/2)时,有sinx〈x〈tanx.  相似文献   

10.
岳优兰  王月山 《数学季刊》1999,14(2):108-110
§1. IntroductionAlocallyintegrablefunctionf(x)belongstoLipα(Rn),ifthereisaconstantC,suchthatforeveryx,y∈Rn|f(x)-f(y)|≤C|x-y|α  ThesmallestconstantCsatisfiesaboveiscalledLipschitznormoffandisdenotedbyyfy∧α.By[1],f∈Lipα(Rn)equivalenttof∈εα,2,whereεα,2=…  相似文献   

11.
陶祥兴 《应用数学》1995,8(4):453-458
本文证明了一类与异性伸缩相关的极大算子在L^p(R^n)上是有界的,其中1〈p≤∝,n≥2。进一步,作为应用我们建立了算子Tf(x)=supε〉0│Tεf(x)│L^p有界性,其中Tε是带有变化核的奇异积分。  相似文献   

12.
关于ψ(z)f(z)f‘(z)的值分布   总被引:3,自引:0,他引:3  
张庆德 《数学学报》1994,37(1):91-98
本文研究有穷圆内ψ(z)f(z)f'(z)的值分布,其中f(z)为非常数亚纯函数,ψ(z)为非零亚纯函数,并对平面上这样的函数,若T(r,ψ)=S(r,f),得到T(r,f)〈9/2N(r,f)+1/2N(r,1/ψff'-1)+S(r,f)。  相似文献   

13.
It is a classical result of Bernstein that the sequence of Lagrange interpolation polumomials to |x| at equally spaced nodes in [-1, 1] diverges everywhere, except at zero and the end-points. In the present paper, toe prove that the sequence of Lagrange interpolation polynomials corresponding to |x|^α (2 〈 α 〈 4) on equidistant nodes in [-1, 1] diverges everywhere, except at zero and the end-points.  相似文献   

14.
设S^*p(β)表示单位圆│Z│〈1内的一族p次对称,正则,单叶,β级星象函数,且H^8p(β)表示单位圆不0〈│z│〈1内的一族p次对称,正则,单叶,β级星象函数。本文得到的一些有关函数族S^*p(β)及H^*p(β)的不等式。这些结果都是精确的。  相似文献   

15.
Let X be a Banach space. If there exists a quotient space of X which is asymptotically isometric to l^1, then X contains complemented asymptotically isometric copies of l^1. Every infinite dimensional closed subspace of l1. contains a complemented subspace of l1 which is asymptotically isometric to l1. Let X be a separable Banach space such that X^* contains asymptotically isometric copies of lp (1 〈 p 〈∞). Then there exists a quotient space of X which is asymptotically isometric to lq (1/p + 1/q=1). Complemented asymptotically isometric copies of co in K(X, Y) and W(X, Y) are discussed. Let X be a Gelfand-Phillips space. If X contains asymptotically isometric copies of co, it has to contain complemented asymptotically isometric copies of co.  相似文献   

16.
我们知道,含有变元的语句不是命题,因为它不能判别真假,如x-3〉0,这不是命题,逻辑上称之为“命题形式”或俗称为“开语句”.这一类语句如果要成为命题,必须前面加上量词,全称量词或存在量词.比如,语句f(x)≥0前面加上全称量词,得全称命题:对所有的x,有f(x)≥0,其否定为存在命题:存在z,有f(x)〈0;  相似文献   

17.
In this paper we give the sufficient and necessary condition for the existence of any almost isometric operator from C(Ω) into C0(Ω0). As a corollary, we show that there is no e-isometry from 1 any abstract M space with a strong unit into C0(Г) if 0 〈 e 〈 1/9.  相似文献   

18.
设μ是R^d上的Randon测度,其唯一需要满足的条件是增长条件:μ(B(z,r))≤Cr”对任意z∈R^d,r〉0成立,0〈n≤d.本文中,在这种非双倍测度下证明了RBMO(μ)与θ(μ型Calderon-Zygmund算子的交换子是L∞(μ)到RBMO(μ)有界的,同时还建立了该交换子H^1 b(μ)到L^1(μ)的有界性.  相似文献   

19.
For 1 〈 p ≤2, an L^p-gradient estimate for a symmetric Markov semigroup is derived in a general framework, i.e. ‖Γ^/2(Ttf)‖p≤Cp/√t‖p, where F is a carre du champ operator. As a simple application we prove that F1/2((I- L) ^-α) is a bounded operator from L^p to L^v provided that 1 〈 p 〈 2 and 1/2〈α〈1. For any 1 〈 p 〈 2, q 〉 2 and 1/2 〈α 〈 1, there exist two positive constants cq,α,Cp,α such that ‖Df‖p≤ Cp,α‖(I - L)^αf‖p,Cq,α(I-L)^(1-α)‖Df‖q+‖f‖q, where D is the Malliavin gradient ([2]) and L the Ornstein-Uhlenbeck operator.  相似文献   

20.
《上海中学数学》2011,(7):23-26,75-80
一、选择题 1.(理)设集合M={χ|χ^2+χ+6〈O},N={χ}≤χ≤3),则M∩N=( )  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