The Ellipsoid Factor for Quantification of Rods, Plates, and Intermediate Forms in 3D Geometries. [PDF]
The Ellipsoid Factor (EF) is a method for the local determination of the rod- or plate-like nature of porous or spongy continua. EF at a point within a 3D structure is defined as the difference in axis ratios of the greatest ellipsoid which fits inside ...
Doube M.
europepmc +6 more sources
Maximum Volume Inscribed Ellipsoid: A New Simplex-Structured Matrix Factorization Framework via Facet Enumeration and Convex Optimization [PDF]
Consider a structured matrix factorization model where one factor is restricted to have its columns lying in the unit simplex. This simplex-structured matrix factorization (SSMF) model and the associated factorization techniques have spurred much interest in research topics over different areas, such as hyperspectral unmixing in remote sensing, topic ...
Chia-Hsiang Lin +4 more
openaire +4 more sources
Computing the Maximum Volume Inscribed Ellipsoid of a Polytopic Projection [PDF]
We introduce a novel scheme based on a blending of Fourier-Motzkin elimination (FME) and adjustable robust optimization techniques to compute the maximum volume inscribed ellipsoid (MVE) in a polytopic projection. It is well-known that deriving an explicit description of a projected polytope is NP-hard.
Jianzhe Zhen, Dick den Hertog
openaire +4 more sources
Sharpening Geometric Inequalities using Computable Symmetry Measures [PDF]
Many classical geometric inequalities on functionals of convex bodies depend on the dimension of the ambient space. We show that this dimension dependence may often be replaced (totally or partially) by different symmetry measures of the convex body ...
Brandenberg, René, König, Stefan
core +1 more source
A Novel Approach for Ellipsoidal Outer-Approximation of the Intersection Region of Ellipses in the Plane [PDF]
In this paper, a novel technique for tight outer-approximation of the intersection region of a finite number of ellipses in 2-dimensional (2D) space is proposed. First, the vertices of a tight polygon that contains the convex intersection of the ellipses
A Kurzhanski +27 more
core +2 more sources
Statistical mechanics for metabolic networks during steady-state growth [PDF]
Which properties of metabolic networks can be derived solely from stoichiometric information about the network's constituent reactions? Predictive results have been obtained by Flux Balance Analysis (FBA), by postulating that cells set metabolic fluxes ...
Andersson, Anna MC +4 more
core +5 more sources
Bezout Inequality for Mixed volumes [PDF]
In this paper we consider the following analog of Bezout inequality for mixed volumes: $$V(P_1,\dots,P_r,\Delta^{n-r})V_n(\Delta)^{r-1}\leq \prod_{i=1}^r V(P_i,\Delta^{n-1})\ \text{ for }2\leq r\leq n.$$ We show that the above inequality is true when ...
Soprunov, Ivan, Zvavitch, Artem
core +3 more sources
On largest volume simplices and sub-determinants [PDF]
We show that the problem of finding the simplex of largest volume in the convex hull of $n$ points in $\mathbb{Q}^d$ can be approximated with a factor of $O(\log d)^{d/2}$ in polynomial time.
Di Summa, Marco +3 more
core +1 more source
Packing ellipsoids with overlap
The problem of packing ellipsoids of different sizes and shapes into an ellipsoidal container so as to minimize a measure of overlap between ellipsoids is considered. A bilevel optimization formulation is given, together with an algorithm for the general
Uhler, Caroline, Wright, Stephen J.
core +1 more source
Quantum steering ellipsoids, extremal physical states and monogamy [PDF]
A Corrigendum for this article has been published in 2015 New J. Phys. 17 019501Any two-qubit state can be faithfully represented by a steering ellipsoid inside the Bloch sphere, but not every ellipsoid inside the Bloch sphere corresponds to a two-qubit ...
Altepeter J +14 more
core +5 more sources

