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相关论文: Convex Polytopes: Extremal Constructions and f-Vec…

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Cyclic polytopes are generally known for being involved in the Upper Bound Theorem, but they have another extremal property which is less well known. Namely, the special shape of their f-vectors makes them applicable to certain…

组合数学 · 数学 2011-07-26 László Major

Weighted cone-volume functionals are introduced for the convex polytopes in $\mathbb{R}^n$. For these functionals, geometric inequalities are proved and the equality conditions are characterized. A variety of corollaries are derived,…

度量几何 · 数学 2023-07-07 Steven Hoehner , Jeff Ledford

We investigate a novel setting for polytope rigidity, where a flex must preserve edge lengths and the planarity of faces, but is allowed to change the shapes of faces. For instance, the regular cube is flexible in this notion. We present…

组合数学 · 数学 2026-03-11 Matthias Himmelmann , Bernd Schulze , Martin Winter

This is a survey on algorithmic questions about combinatorial and geometric properties of convex polytopes. We give a list of 35 problems; for each the current state of knowledege on its theoretical complexity status is reported. The…

组合数学 · 数学 2007-05-23 Volker Kaibel , Marc E. Pfetsch

The objective of this paper is to present two types of results on Minkowski sums of convex polytopes. The first is about a special class of polytopes we call perfectly centered and the combinatorial properties of the Minkowski sum with…

组合数学 · 数学 2009-02-14 Komei Fukuda , Christophe Weibel

In this paper, we show that if we decompose a polygon into two smaller polygons, then by comparing the number of extremal vertices in the original polygon versus the sum of the two smaller polygons, we can gain at most two globally extremal…

度量几何 · 数学 2010-04-13 Wiktor J. Mogilski

We introduce a deformed product construction for simple polytopes in terms of lower-triangular block matrix representations. We further show how Gale duality can be employed for the construction and for the analysis of deformed products…

度量几何 · 数学 2012-12-27 Raman Sanyal , Günter M. Ziegler

New superconvergent structures are introduced by the finite volume element method (FVEM), which allow us to choose the superconvergent points freely. The general orthogonal condition and the modified M-decomposition (MMD) technique are…

数值分析 · 数学 2022-05-25 Xiang Wang , Junliang Lv , Yonghai Li

This article introduces the theory of Veronese polytopes, a broad generalisation of cyclic polytopes. These arise as convex hulls of points on curves with one or more connected components, obtained as the image of the rational normal curve…

组合数学 · 数学 2024-11-22 Marie-Charlotte Brandenburg , Roland Púček

This dissertation investigates the geometric combinatorics of convex polytopes and connections to the behavior of the simplex method for linear programming. We focus our attention on transportation polytopes, which are sets of all tables of…

组合数学 · 数学 2010-06-15 Edward D. Kim

This paper develops novel natural superconvergence and ultraconvergence structures for the bi-$k$-order finite volume element (FVE) method on rectangular meshes. These structures furnish tunable and possibly asymmetric superconvergence and…

数值分析 · 数学 2025-10-14 Xiang Wang , Yuqing Zhang , Zhimin Zhang

We obtain computational hardness results for f-vectors of polytopes by exhibiting reductions of the problems DIVISOR and SEMI-PRIME TESTABILITY to problems on f-vectors of polytopes. Further, we show that the corresponding problems for…

组合数学 · 数学 2021-09-20 Eran Nevo

We wish to draw attention to an interesting and promising interaction of two theories. On the one hand, it is the theory of \textbf{pseudo-triangulations} which was useful for implicit solution of thecarpenter's rule problem and proved…

度量几何 · 数学 2007-05-23 Gaiane Panina

We study the slices or sections of a convex polytope by affine hyperplanes. We present results on two key problems: First, we provide tight bounds on the maximum number of vertices attainable by a hyperplane slice of $d$-polytope (a sort of…

组合数学 · 数学 2025-07-24 Jesús A. De Loera , Gyivan Lopez-Campos , Antonio J. Torres

This research will be helpful for people to display the 2-dimensiona projective models of 4-variable actual problems in many fields, in order to investigate deeply those actual problems. By using the theory of N-dimensional finite rotation…

综合数学 · 数学 2009-06-13 Kaida Shi

We study the extreme points of the cone of quasiconvex quadratic forms with linear elastic orthotropic symmetry. We prove that if the determinant of the acoustic matrix of the associated forth order tensor of the quadratic form is an…

偏微分方程分析 · 数学 2019-06-19 Davit Harutyunyan

The aim of this paper is to study alcoved polytopes, which are polytopes arising from affine Coxeter arrangements. This class of convex polytopes includes many classical polytopes, for example, the hypersimplices. We compare two…

组合数学 · 数学 2007-05-23 Thomas Lam , Alexander Postnikov

The Four-Vertex Theorem has been of interest ever since a discrete version appeared in 1813 due to Cauchy. Up until now, there have been many different versions of this theorem, both for discrete cases and smooth cases. In 2004, an approach…

度量几何 · 数学 2009-06-15 Wiktor J. Mogilski

We study the maximum weight convex polytope problem, in which the goal is to find a convex polytope maximizing the total weight of enclosed points. Prior to this work, the only known result for this problem was an $O(n^3)$ algorithm for the…

计算几何 · 计算机科学 2022-07-27 Mohammad Ali Abam , Ali Mohammad Lavasani , Denis Pankratov

We call a polytope P of dimension 3 admissible if it has the following two properties: (1) for each vertex of P the set of its first-neighbours is coplanar; (2) all planes determined by the first-neighbours are distinct. It is shown that…

组合数学 · 数学 2012-07-31 Gábor Gévay , Tomaž Pisanski