正定Hermite矩阵的若干行列式不等式

本文对满足条件Ａ^Ｈ＝Ａ＞０，１／２（Ｂ＋Ｂ^Ｈ）≥０的矩阵Ａ，Ｂ，建立了四个行列式不等式．某些著名的行列式不等式和一些已知结用，均可作为其推论．     

关于含有Stirling公式的双边不等式(英)

本文证明了有关n！的一个便于应用的双边不等式,它对一切自然数都成立,且当n变大时,上界不等式能给出误差界为O（n^－3）的Stirling渐近公式,从一定意义上说,文中的上界不等式具有最优形式,因为其中的常数0．5已作了最佳选择．文末还给出了关于Catalan数的一个双边不等式．     

Belman不等式(I)

本文考察不等式：ｔｒ（ＡＢ）^ｍ≤ｔｒ（Ａ^ｍＢ^ｍ），ｍ＝１，２，３，…，其中Ａ，Ｂ为Ｋ阶方阵．证明了当Ａ正定Ｂ对称幂等条件下上述不等式成立．还考察了Ａ，Ｂ为非负矩阵时的情形     

三角不等式

用不等号连接的古有三角函数的式子简称为兰角不等式．在我国高中数学竞赛中．关于兰角不等式的问题有三类，一是三角不等式的证明．二是解三角不等式．兰是应用三角三不等式求最值．处理这三类问题，既要用到不等式的有关性质，又耍熟练运用三角公式进行恒等变形，有时还要利用三角函数的图象和性质．     

一道数学竞赛题的联想

用级数方法证明了一个三角不等式，同时还得到了几个新的三角不等式．     

一类分层三角剖分下三次样条空间的维数

本文定义了平面单连通多边形域的一类较任意的三角剖分－分层三角剖分，并通过分析二元样条的积分协调条件，确定了分层三角剖分卜三次Ｃ^１作条函数空间的维数．     

关于Vitali族的分数次极大算子的加权模不等式

设(?)是Ｒ^ｎ中的Ｖｉｔａｌｉ族，０≤γ≤１，定义分数次极大算子如下：本文得到了上述分数次极大算子的加权弱型不等式和加权强型不等式．     

关于二元样条空间Sr（3r）（△*）的维数

设△^*任何三角剖分△的ＨＣＴ细分的三角剖分．本文建立了定义于△^*上的二元样条函数空间S^r_（3r）（△^*）的维数公式．我们的证明方法同时给出了S^r_（3r）（△^*）的一组显示的基函数，并阐明基函数具有某种意义的局部最小支集     

L2空间中的Bernstein─Markov不等式及其最佳常数（Ⅱ）

继［１５］．本中考虑了带不同权函数L²[-1,1]空间中的Ｂｅｒｎｓｔｃｉｎ－Ｍａｒｋｏｖ不等式，给出了其最佳常数；最后还得到相应的反向Ｂｅｒｎｓｔｃｉｎ－Ｍａｒｋｏｖ不等式．     

关于单形空间角的准正弦概念及应用

建立了欧氏空间Ｅ^ｎ中ｎ维单形空间角的准正弦概念，并应用于高维正弦定理的改进、Ｓｔｅｉｎｅｒ定理的高维推广及切点不等式的简化证明；又推出了有关单形的一些新不等式．     

Sharp convex Lorentz–Sobolev inequalities

New sharp Lorentz–Sobolev inequalities are obtained by convexifying level sets in Lorentz integrals via the L ^p Minkowski problem. New L ^p isocapacitary and isoperimetric inequalities are proved for Lipschitz star bodies. It is shown that the sharp convex Lorentz–Sobolev inequalities are analytic analogues of isocapacitary and isoperimetric inequalities.     

Hardy-Sobolev type inequalities on the H-type group

Motivated by the idea of Badiale and Tarantello who have found Hardy-Sobolev inequalities on Rⁿ, a class of Hardy-Sobolev type inequalities on H-type groups is proved via a new representation formula for functions. Extremal functions realizing equality in the inequalities are discussed by refined Concentration-Compactness principles. Finally, some sharp constants for Hardy type inequalities are given. The project supported by National Natural Science Foundation of China, Grant No. 10371099.     

<Emphasis Type="Italic">L</Emphasis><Superscript><Emphasis Type="Italic">p</Emphasis></Superscript>-Poincaré inequality for general symmetric forms

Lp Poincare inequalities for general symmetric forms are established by new Cheeger＇s isoperimetric constants. Lp super-Poincare inequalities are introduced to describe the equivalent conditions for the Lp compact embedding, and the criteria via the new Cheeger＇s constants for those inequalities are presented. Finally, the concentration or the volume growth of measures for these inequalities are studied.     

Norm inequalities in operator ideals

In this paper we introduce a new technique for proving norm inequalities in operator ideals with a unitarily invariant norm. Among the well-known inequalities which can be proved with this technique are the Löwner-Heinz inequality, inequalities relating various operator means and the Corach-Porta-Recht inequality. We prove two general inequalities and from them we derive several inequalities by specialization, many of them new. We also show how some inequalities, known to be valid for matrices or bounded operators, can be extended with this technique to normed ideals in C^∗-algebras, in particular to the noncommutative Lp-spaces of a semi-finite von Neumann algebra.     

Note on Affine Gagliardo–Nirenberg Inequalities

This note proves sharp affine Gagliardo–Nirenberg inequalities which are stronger than all known sharp Euclidean Gagliardo–Nirenberg inequalities and imply the affine L ^p -Sobolev inequalities. The logarithmic version of affine L ^p -Sobolev inequalities is verified. Moreover, an alternative proof of the affine Moser–Trudinger and Morrey–Sobolev inequalities is given. The main tools are the equimeasurability of rearrangements and the strengthened version of the classical Pólya–Szegö principle.     

Exact inequalities for splines and best quadrature formulas for certain classes of functions

In this note inequalities between the norms of a spline and its derivatives in various Orlich spaces are obtained. These inequalities are analogs of the inequalities of L. V. Takov for trigonometrical polynomials and generalize S. N. Bernstein's inequalities. An inequality for monosplines which reduces to the best quadrature formula for the classes W^rL₁, where r=1, 2,..., is also obtained. For r=2, 4, 6, ... this result was obtained earlier by V. P. Motornyi.Translated from Matematicheskie Zametki, Vol. 19, No. 6, pp. 913–926, June, 1976.     

Interpolation inequalities and decay estimates for derivatives

Under the only assumption of the cone property for a given domain Ω⊂R ⁿ, it is proved that interpolation inequalities for intermediate derivatives of functions in the Sobolev spaces W^m,p (Ω) or even in some weighted Sobolve spaces W _w ^m,p (Ω) still hold. That is, the usual additional restrictions that Ω is bounded or has the uniform cone property are both removed. The main tools used are polynomial inequalities, by which it is also obtained pointwise version interpolation inequalities for smooth and analytic functions. Such pointwise version inequalities give explicit decay estimates for derivatives at infinity in unbounded domains which have the cone property. As an application of the decay estimates, a previous result on radial basis function approximation of smooth functions is extended to the derivative-simultaneous approximation.     

Some Bonnesen-style inequalities for higher dimensions

We discuss the higher dimensional Bonnesen-style inequalities.Though there are many Bonnesen-style inequalities for domains in the Euclidean plane R2 few results for general domain in R n(n ≥ 3) are known.The results obtained in this paper are for general domains,convex or non-convex,in Rn.     

Sharp constants for Moser‐Trudinger inequalities on spheres in complex space ℂn

The main results of this paper concern sharp constants for the Moser‐Trudinger inequalities on spheres in complex space ?ⁿ. We derive Moser‐Trudinger inequalities for smooth functions and holomorphic functions with different sharp constants (see Theorem 1.1). The sharp Moser‐Trudinger inequalities under consideration involve the complex tangential gradients for the functions and thus we have shown here such inequalities in the CR setting. Though there is a close connection in spirit between inequalities proven here on complex spheres and those on the Heisenberg group for functions with compact support in any finite domain proven earlier by the same authors [17], derivation of the sharp constants for Moser‐Trudinger inequalities on complex spheres are more complicated and difficult to obtain than on the Heisenberg group. Variants of Moser‐Onofri‐type inequalities are also given on complex spheres as applications of our sharp inequalities (see Theorems 1.2 and 1.3). One of the key ingredients in deriving the main theorems is a sharp representation formula for functions on the complex spheres in terms of complex tangential gradients (see Theorem 1.4). © 2004 Wiley Periodicals, Inc.     

Isoperimetric monotony of the L p -norm of the warping function of a plane simply connected domain

Let G be a simply connected domain and let u(x,G) be its warping function. We prove that L ^p -norms of functions u and u ^?1 are monotone with respect to the parameter p. This monotony also gives isoperimetric inequalities for norms that correspond to different values of the parameter p. The main result of this paper is a generalization of classical isoperimetric inequalities of St.Venant-Pólya and the Payne inequalities.