Estimates for Some Functionals of Bounded Nonvanishing Functions

We consider the class of bounded nonvanishing analytic functions in the unit disk and study the properties of extremal functions for some functionals of a certain form on this function class.     

Coefficient Estimates for Bi-Univalent Bazilevic Functions

In this paper we consider the class of Bazilevic functions for bi-univalent functions. For this we will estimate the coefficients a2 and a3 using Caratheodory func- tions and the method of differential subordination.     

Coefficient Estimates for Two Subclasses of Analytic and Bi-Univalent Functions

Ukrainian Mathematical Journal - We introduce two new subclasses of the class ?? of analytic and bi-univalent functions in the open unit disk U. Furthermore, we establish estimates...     

几类亚纯双单叶函数的系数估计

研究了几类亚纯双单叶函数的系数估计,所得结果改进或推广了部分作者的结论.     

Local Lower Norm Estimates for Dyadic Maximal Operators and Related Bellman Functions

We provide lower \(L^{q}\) and weak \(L^{q}\)-bounds for the localized dyadic maximal operator on \(\mathbb {R}^{n}\), when the local \(L^{1}\) and the local \(L^{p}\) norms of the function are given. We actually do that in the more general context of homogeneous trees in probability spaces.     

Norm Estimates for Weighted Composition Operators on Spaces of Holomorphic Functions

This paper shows that the boundedness of a weighted composition operator on the Hardy–Hilbert space on the disc or half-plane implies its boundedness on a class of related spaces, including weighted Bergman spaces. The methods used involve the study of lower-triangular and causal operators.     

导子的范数估计

本文给出了因子 ｖｏｎ Ｎｅｕｍａｎｎ代数中套子代数上导子的范数估计．利用此结果得到一个距离公式,并证明了因子 ｖｏｎ Ｎｅｕｍａｎｎ代数中的任何套子代数都具有ＡＩＰ（ｒ, ｓ）性质     

Coefficient Estimates for Certain Subclasses of Bi-Univalent Ma-Minda Mocanu-Convex Functions

In this paper, we introduce and investigate a new subclass of the function class Σ of bi-univalent functions of the Mocanu-convex type defined in the open unit disk, satisfy Ma and Minda subordination conditions. Furthermore, we find estimates on the Taylor-Maclaurin coefficients |a2| and |a3| for functions in the new subclass introduced here. Further Application of Hohlov operator to this class is obtained. Several(known or new) consequences of the results are also pointed out.     

On The Exact Norm Value Op Some Bmoa Functions

In this paper we construct two large classes of BMOA functions with BMOA norm equal to the H² norm, respecting equal to the H^∞ norm. We also determine all functions in the disc algebra with BMOA norm equal to the Bloch norm.     

有界格上的一些函数与几个半群

在有界格上引进了6个函数(算子),研究了它们之间的关系,并且得到了几个半群．     

基于Salagean算子的bi-单叶函数系数估计

讨论和研究了受限于Salagean算子且同时满足:1+1/b((D~(n+1)f(z)/(D~nf(z)))-1)φ(z)和1+1/b((D~(n+1)f~(-1)(ω)/(D~nf~(-1)(ω))-1)Ψ(ω)的bi-单叶解析函数的系数估计问题,这里φ(z)和Ψ(ω)为正实部函数.主要的研究结果直接推广了先前相应工作.     

Some Sharp Norm Estimates in the Subspace Perturbation Problem

We discuss the spectral subspace perturbation problem for a self-adjoint operator. Assuming that the convex hull of a part of its spectrum does not intersect the remainder of the spectrum, we establish an a priori sharp bound on variation of the corresponding spectral subspace under off-diagonal perturbations. This bound represents a new, a priori, tan Θ Theorem. We also extend the Davis–Kahan tan 2Θ Theorem to the case of some unbounded perturbations.     

与条形区域有关的双向单叶解析函数子类的系数估计

本文引入了条形区域内由Salagean算子刻画的解析函数新子类, 讨论了该函数子类的系数估计、Fekete-Szego不等式以及与该函数子类有关的双向单叶函数的系数估计, 所得结果推广了前人的一些工作.     

Estimates for coefficients of univalent functions from integral means and Grunsky inequalities

Sharp bounds are obtained for the coefficients of inverses of univalent functions in the class Σ(p) by using results on integral means and generalized Grunsky inequalities. A new and elementary proof is given for a result due to Löwner about sharp bounds for coefficients of inverses of functions in the classS.     

Some Estimates for the Norm of the Bergman Projection on Besov Spaces

In this paper we obtain an estimate of the norm of the Bergman projection from L ^p (D, dλ) onto the Besov space B _p , 1 < p < + ∞. The result is asymptotically sharp when p → + ∞. Further for the case P : L ¹(D, dλ) → B ₁, we consider some weak type inequalities with the corresponding spaces.     

卷入Hohlov算子的某解析双单叶函数子类的系数估计*

本文引入并研究卷入 Hohlov 算子的解析双单叶函数类Σ的新子类S^a,b,c_Σ(τ, μ, λ, γ; φ),然后得到其对应的系数a₂ 和a₃的有界估计. 进而,一些与早期已有结果的因果关系和联系也被给出.     

Boundary Problems for Harmonic Functions and Norm Estimates for Inverses of Singular Integrals in Two Dimensions

In this paper, we establish sharp well-posedness results for tangential derivative problems for the Laplacian with data in L ^p , 1 < p < ∞, on curvilinear polygons. Furthermore, we produce norm estimates/formulas for inverses of singular integral operators relevant for the Dirichlet, Neumann, tangential derivative, and transmission boundary value problems associated with the Laplacian in a distinguished subclass of Lipschitz domains in two dimensions. Our approach relies on Calderón-Zygmund theory and Mellin transform techniques.