具广义Calderón-Zygmund核的多线性振荡奇异积分极大算子的有界性

本文研究了具有广义Calderón-Zygmund核的多线性奇异积分极大算子和多线性振荡奇异积分极大算子,证明了这类极大算子的Lp-有界性.     

几类多线性算子在B_σ-Morrey空间上的有界性

研究了多线性Hardy-Littlewood极大算子,多线性分数次极大算子,多线性奇异积分和分数次积分算子在Bσ-Morrey空间上的有界性.     

θ型Calderón-Zygmund核的多线性奇异积分极大算子的Lp-有界性

研究了θ型Calderón-Zygmund核的多线性奇异积分极大算子,证明了这类极大算子的Lp-有界性.     

$\theta$型Calderon-Zygmund核的多线性奇异积分极大算子的$L^{p}$-有界性

研究了$\theta$型Calderon-Zygmund核的多线性奇异积分极大算子, 证明了这类极大算子的$L^{p}$-有界性.     

多重奇异积分与Lipschitz函数生成的多线性交换子

本文研究了由多重奇异积分和Lipschitz函数生成的多线性交换子.利用Hardy-Littlewood极大算子的有界性,得到了交换子从Lebesgue积空间到Lebesgue空间的有界性,推广了文献[16]的结果.     

沿复合子簇的粗糙核极大算子

给出了两类相关于沿复合子簇的粗糙核奇异积分的极大算子的L~p有界性,本质上极大地改进和一般化了已有的结果.作为应用,相关的奇异积分,Marcinkiewicz积分和相应的极大算子的L~p有界性也被建立.     

多线性算子在Herz型Hardy空间上的有界性

本文证明了Ｒｎ上奇异积分乘积之有限和的多线性算子是从ＨＫｑ１α１,ｐ１（Ｒｎ）×… ×ＨＫｑｋαｋ,ｐｋ（Ｒｎ）到ＨＫｑα,ｐ（Ｒｎ）有界的,如果它满足由目标空间所确定的直到一定阶的消失矩条件．这些多线性算子所满足的消失矩条件,当αｊ≥０时也是必要的．而且,这里所考虑的奇异积分包括Ｃａｌｄｅｒｏｎ－Ｚｙｇｍｕｎｄ奇异积分及任意阶的分数次积分．     

Hardy空间上的多线性振荡奇异积分算子

本文考虑与振荡奇异积分相关的一些多线性算子在Ｈａｒｄｙ空间Ｈ１（Ｒｎ）上的性质     

极大多线性奇异积分算子的一些点态估计

建立了联系极大多线性奇异积分算子与某些古典极大算子的两个点态估计, 这些点态估计隐含着极大多线性奇异积分算子的重排估计和BLO(Rⁿ)估计.     

多线性向量值奇异积分极大算子的加权不等式

本文研究向量值奇异积分极大多线性交换子的性质,得到该算子的加权估计及加权弱型估计,作为该估计的推论可知算子T_(q,(?))~*在L~p(ω)上有界,其中ω∈A_p。当ω∈A_1时,满足加权L(logL)~(1/r)型估计。     

弱Hardy空间上多线性分数次积分算子的有界性

本文研究了弱Hardy空间上多线性分数次积分算子和相应的多线性分数次极大算子的有界性,利用多线性分数次积分转化为相对应的分数次积分的方法,得到算子TΩ,α,A和MΩ,α,A的弱型估计.     

r阶二进求导极大算子的有界性

本文研究了r阶二进求导极大算子的有界性.利用Dirichlet核的性质证明了此极大算子在一维和d维情况下都不是从Hardy空间Hp到Hardy空间Hp有界的,其中0相似文献   

The discrete maximal operator in metric spaces

We study the action of the so-called discrete maximal operator on Newtonian, Hölder and BMO spaces on metric measure spaces equipped with a doubling measure and a Poincaré inequality. The discrete maximal operator has better regularity properties than the standard Hardy-Littlewood maximal operator and hence is a more flexible tool in this context.     

Krein空间中无穷维Hamilton算子的极大确定不变子空间的存在性问题

本文研究了不定度规空间空间中的无穷维Hamilton算子.利用Plus算子存在极大不变子空间的性质,获得了无穷维Hamilton算子在Krein空间中存在极大确定不变子空间的充分条件.     

2 × 2 算子矩阵的正性*

本文主要研究 2 × 2 算子矩阵的正性,并利用极大Tseng逆理论等给出了 2 × 2 算子矩阵为正算子的等价条件.此外, 给出一类正算子矩阵的平方根算子表达式.     

与极大四瓦片算子有界性相关的某些原理

本文研究了极大四瓦片算子的线性化过程.利用一族线性算子的一致有界性,获得了极大四瓦片算子的强型估计和弱型估计.并且指出了文献[1,2]中的某些错误.     

Multiple weighted estimates for maximal vector-valued commutator of multilinear Calderón-Zygmund singular integrals

This paper concerns with multiple weighted norm inequalities for maximal vector-valued multilinear singular operator and maximal commutators. The Cotlar-type inequality of maximal vector-valued multilinear singular integrals operator is obtained. On the other hand, pointwise estimates for sharp maximal function of two kinds of maximal vector-valued multilinear singular integrals and maximal vector-valued commutators are also established. By the weighted estimates of a class of new variant maximal operator, Cotlar's inequality and the sharp maximal function estimates, multiple weighted strong estimates and weak estimates for maximal vector-valued singular integrals of multilinear operators and those for maximal vector-valued commutator of multilinear singular integrals are obtained.     

Dissipative operators in the Krein space. Invariant subspaces and properties of restrictions

We prove that a dissipative operator in the Krein space has a maximal nonnegative invariant subspace provided that the operator admits matrix representation with respect to the canonical decomposition of the space and the upper right operator in this representation is compact relative to the lower right operator. Under the additional assumption that the upper and lower left operators are bounded (the so-called Langer condition), this result was proved (in increasing order of generality) by Pontryagin, Krein, Langer, and Azizov. We relax the Langer condition essentially and prove under the new assumptions that a maximal dissipative operator in the Krein space has a maximal nonnegative invariant subspace such that the spectrum of its restriction to this subspace lies in the left half-plane. Sufficient conditions are found for this restriction to be the generator of a holomorphic semigroup or a C ₀-semigroup.     

Principal currents

An operator theoretic analog of a local Chern class is discussed for certain finitely generated operator algebras. This gives rise to an index theory for the maximal ideals of the algebra. The algebraic receiver for this index is the Grothendieck group of the algebra completed at a maximal ideal.This research was partially supported by grants from the National Science Foundation.     

Sobolev spaces, Lebesgue points and maximal functions

In this note, we study boundedness of a large class of maximal operators in Sobolev spaces that includes the spherical maximal operator. We also study the size of the set of Lebesgue points with respect to convergence associated with such maximal operators.