关于L_p-混合质心体的Busemann-Petty问题

对p≥1,Lutwak和Zhang引进了R~n中一个星体K的L_p-质心体Γ_pK的概念,Grinberg和Zhang研究了L_p-质心体算子Γ_p的Busemann-Petty问题;最近,马统一引进了星体K的L_p-混合质心体Γ_(p,i)K(i∈R)的概念,即L_p-质心体是它的特殊类.本文研究了Γ_(p,i)K(?)Γ_(p,i)L是否一定(?)的问题.其结果是Grinberg和Zhang关于L_p-质心体算子Γ_p的Busemann-Petty问题的推广形式.     

L_p-混合质心体和对偶L_p-混合质心体

本文引进了L_p-混合质心体Γ_(p,i)K、对偶L_p-混合质心体Γ_(-p,i)K和R~n中星体K和L的L_p-混合调和Blaschke加K+_pL的概念,成功地解决了L_p-混合质心体和对偶L_p-混合质心体的Shephard型问题.并且结合星体的L_p-混合调和Blaschke加的概念,分别建立了L_p-混合质心体的均质积分和对偶均质积分的Brunn-Minkowski型不等式.所获结论推广了已有文献的结果.     

混合新几何体Γ_(-p，i)K的不等式

近来,Lutwak,Yang和Zhang提出了新几何体Γ_(-p)K的概念,获得一些结论.本文引入混合新几何体Γ_(-p,i)K的概念,即新几何体是它的特殊类,得到了混合新几何体的一些性质,并建立了相关的不等式.     

关于新几何体Γ_(-p)K的几个不等式

本文研究了新几何体Γ_(-p)K与L_p-质心体和L_p-John椭球有关的几个有趣不等式,包括L_p-Busemann-Petty质心不等式的一种隔离,同时探讨了新几何体Γ_(-p)K的单调性．     

关于L_p-极投影体Shephard问题的一个类似（英文）

For p 0, Lutwak, Yang and Zhang introduced the concept of L_p-polar projection body Γ_(-p)K of a convex body K in Rn. Let p ≥ 1 and K, L ? Rnbe two origin-symmetric convex bodies, we consider the question of whether Γ_(-p) K ? Γ_(-p) L implies ?_p(L) ≤ ?_p(K),where ?_p(K) denotes the L_p-affine surface area of K and K = Voln(K)~(-1/p) K. We prove a necessary and sufficient condition of an analog of the Shephard problem for the L_p-polar projection bodies.     

椭球的Orlicz质心体(英文)

主要研究了Lutwak等所引入的Orlicz质心体(Lutwak E,Yang D,Zhang G.Orliczcentroid bodies.J.Differential Geom.,2010,84:365-387).利用Orlicz质心体在线性变换下的不变性,证明了椭球的Orlicz质心体仍是椭球.作为例子,计算了当取两个特定的凸函数时单位球的Orlicz质心体的支持函数.     

Lp-投影体的均质积分和对偶均质积分的Brunn-Minkowski不等式

在Lutwak,Yang和Zhang提出的Lp-投影体概念的基础上结合凸体的Blaschke Lp-组合.分别得到了Lp-投影体的均质积分和对偶均质积分的Brunn-Minkowski不等式.另外,还给出了关于Lp-投影体的均质积分和对偶均质积分的单调性不等式.     

关于L_p-相交体的Busemann-Petty型问题(英文)

Haberl and Ludwig introduced the L_p-intersection body I_pK for an originsymmetric star body K in R~n,where p < 1 and p ≠ 0.In this paper,we consider the Busemann-Petty’s problem for L_p-intersection bodies I_pK and I_pL.That is,whether I_pK ■ IpL implies Vol_n(K) ≤ Vol_n(L).We obtain that for two origin-symmetric star bodies K and L in R~n,such that(R~n,||·||K) embeds in L_p and I_pK ■ IpL,then vol_n(K) ≤ vol_n(L) for 0 < p < 1 and vol_n(K) ≥ vol_n(L) for p < 0.     

对偶均值积分的Marcus-Lopes不等式

Milman曾提出过一个问题;在混合体积理论,是否存在Marcus-Lopes型和Bergstrom型不等式?即对R~n上任意凸体K与L且i=0,…,n-1,是否成立(W_i(K+L))/(W_i+1(K+L))≥(W_i(K))/(W_i+1(K))+(W_i(L))/(W_i+1(L))?这里W_i表示凸体的i次均值积分.当且仅当i=n-1或i=n-2时,这个问题是正确的,已被证明.作者考虑了一个对偶问题,证明了:若K与L是R~n上的星体,n-2≤i≤n-1且i∈R,则(W_i(K+L))/(W_i+1(K+L))≤(W_i(K))/(W_i+1(K))+(W_i(L))/(W_i+1(L))/(W_i+1(L))其中W_i表示星体的i次对偶均值积分.     

双曲问题边界条件的均匀化

本文对于双曲问题讨论边界条件的均匀化问题。设边界=(?)Ω可表为Γ=Γ_1∪Γ_2∪Γ_3,Γ_1∩Γ_3=φ。(?)ε>0,将分为和,並在其上给出不同的边界条件。我们对于几种不同的情形讨论了随的来种测度趋于零时(当ε→0时)解的极限性态。     

The Petty Projection Inequality for Lp-Mixed Projection Bodies

Recently, Lutwak, Yang and Zhang posed the notion of Lp-projection body and established the Lp-analog of the Petty projection inequality. In this paper, the notion of Lp-mixed projection body is introduced--the Lp-projection body being a special case. The Petty projection inequality, as well as Lutwak＇s quermassintegrals （Lp-mixed quermassintegrals） extension of the Petty projection inequality, is established for Lp-mixed projection body.     

The logarithmic Minkowski problem for polytopes

The logarithmic Minkowski problem asks for necessary and sufficient conditions for a finite Borel measure on the unit sphere so that it is the cone-volume measure of a convex body. This problem was solved recently by Böröczky, Lutwak, Yang and Zhang for even measures (Böröczky et al. (2013) [8]). This paper solves the case of discrete measures whose supports are in general position.     

On the reverse Orlicz Busemann–Petty centroid inequality

In this paper, the Orlicz centroid body, defined by E. Lutwak, D. Yang and G. Zhang, and the extrema of some affine invariant functionals involving the volume of the Orlicz centroid body are investigated. The reverse form of the Orlicz Busemann–Petty centroid inequalities is obtained in the two-dimensional case.     

投影体与U(P)的极值性质

为了研究著名的Schneider投影问题,E.Lutwak,D.Yang和张高勇最近引进了一个关于对称多胞形的新的仿射不变量U(P),并提出了关于U(P)下界的猜想.本文就二维、三维在一特定条件下的情形给予了此猜想的肯定回答并给出了严格的数学证明.     

A probabilistic take on isoperimetric-type inequalities

We extend a theorem of Groemer on the expected volume of a random polytope in a convex body. The extension involves various ways of generating random convex sets. We also treat the case of absolutely continuous probability measures rather than convex bodies. As an application, we obtain a new proof of a recent result due to Lutwak, Yang and Zhang on the volume of Orlicz-centroid bodies.