Reduction of operator families to integral form

We establish a condition for reducibility of a family of operators to integral form by an isometric operator the same for the whole family.     

Integral Operators and Absolute Convergence Systems

We use some integral operators to establish a few special properties of absolute convergence systems for l ².     

Some necessary and sufficient conditions for Hypercyclicity Criterion

We give necessary and sufficient conditions for an operator on a separable Hilbert space to satisfy the hypercyclicity criterion. This paper is a part of the second author’s Doctoral thesis, written at Shiraz University under the direction of the first author.     

A Generalization of the Weighted Hardy Inequality for One Class of Integral Operators

We consider the problem of finding necessary and sufficient conditions for validity of an estimate for a function by some differential operation containing a weight function rather than the ordinary derivative. This operation is referred to as the -weighted derivative.     

线性算子的摄动定理

该文利用Mbekhta M于1987年引入的两个子空间来研究线性算子的摄动. 证明了如下结论：设X=K(T)+W, 其中K(T), W均闭, dim［K(T)∩N(T)］< ∞. 若TWW, TW闭, 且存在闭子空间N, 使W=［W∩N(T)］N, 则： 当S∈B(X)可逆, ST= TS, SWW, 且‖S‖充分小时， T-S为上半Fredholm算子. 在上条件下, 若dimN<∞, K(T′)闭, 则T-S为Fredholm算子, 且R(T-S)=X.     

保矩阵{1}逆的线性映射

设R是特征为2的主理想整环,Mn(R)表示R上n×n矩阵代数,在本文中我们给出了保Mn(R)中矩阵{1}逆的线性映射的一个刻划.     

On the functions of one selfadjoint integral operator

We construct a selfadjoint Akhiezer integral operator S on L ₂(?1, 1) with the spectrum {?1; 0; 1} and the property that every function φ(S) that is not a multiple of S fails to be an Akhiezer integral operator.     

On the Similarity between Volterra Operators and Transformation Operators for Integro-Differential Operators of Fractional Order

We establish the similarity between certain Volterra integral operators and the Riemann--Liouville fractional integration operator as well as the existence of a triangular transformation operator for integro-differential equations of fractional order. The results obtained are consistent with similar results for the case of integer order.     

单位球的Bergman空间上Schatten类加权复合算子

本文研究了单位球的Bergman空间上Schatten类加权复合算子,得到了这种加权复合算子属于Schatten-Von Neumann.理想S_p的几个充要条件.作为推论给出了Wφ,φ是一个Hilbert- Schmidt算子的充要条件是∫_(Bn)(|ψ(ω)|~2)/((1-|φ(ω)|~2)~(n 1)dV(ω)<∞..     

Boundedness Criterion for Some Commutators of Linear Operators

The paper is to establish a boundedness criterion for some commutators of linear operators when these linear operators don't satisfy the general A_p weight estimates but satisfy some radial weight estimates.     

Boundedness Criterion for Some Commutators of Linear Operators

The paper is to establish a boundedness criterion for some commutators of linear operators when these linear operators don't satisfy the general A_p weight estimates but satisfy some radial weight estimates.     

A_α~2上复合算子的Hilbert-Schmidt差分

本文设A_α~2为定义在n维复空间单位多圆柱上的加权Bergman空间,L为Bergman空间上有界复合算子的全体并赋予算子范数拓扑,应用复合算子的HilbertSchmidt差分研究L的拓扑连通性.     

极大算子的加权BLO估计(英文)

引入加权BLO空间,得到了极大奇异积分算子和Hardy-Littlewood极大算子的加权BLO估计.     

On the Integral Operators of the Third Kind

We establish some necessary and sufficient conditions for an operator in the space of square summable functions to be representable as a sum of multiplication by a bounded function and an integral operator.     

Prediction Operators in Banach Ideal Spaces

A necessary and sufficient condition for an operator in a Banach ideal space to be a prediction operator is given.     

有界线性算子非负分裂的比较

本文研究有界线性算子非负分裂的比较,建立了若干比较定理,给出了保证两个迭代算子的谱半径间严格不等式成立的一些充分条件．这些结论蕴涵并推广了Ｍａｒｅｋ 和Ｓｚｙｌｄ［２］以及作者［４］的相应结果     

利用微积分算子求幂级数的和函数

针对幂级数求和函数的问题,引入借助微分算子、积分算子和微分方程进行计算的方法,可作为逐项微分法和逐项积分法的一种补充．实例说明其应用．     

L~p Estimates for Hyperbolic Singular Integral Operators

In this paper, we prove Lp-boundedness of hyperbolic singular integral operators for kernels satisfying weakened regularity conditions, where 1相似文献   

Pointwise Estimates for Linear Combinations of Gamma Operators

For linear combinations of Gamma operators G_n,r(f,x), we give an equivalent theorem with (f,t), where (f,t) are the Ditzian-Totik moduli of smoothness ( ).AMS Subject Classification (1991): 41A25, 41A36.Supported by NSF of Hebei ProvinceSupported by NSF of Hebei Province     

Pointwise Estimate for Linear Combinations of Bernstein-Kantorovich Operators

For linear combinations of Bernstein-Kantorovich operators K_n, r(f, x), we give an equivalent theorem with ω^2r_?^λ(f, t). The theorem unites the corresponding results of classical and Ditzian-Totik moduli of smoothness.