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The convergence of the projection algorithm for solving the convex feasibility problem for a family of closed convex sets, is in connection with the regularity properties of the family. In the paper [18] are pointed out four cases of such a…

Numerical Analysis · Computer Science 2009-06-01 Laura Maruster , Stefan Maruster

Let $P$ be a planar set of $n$ points in general position. We consider the problem of computing an orientation of the plane for which the Rectilinear Convex Hull of $P$ has minimum area. Bae et al. (Computational Geometry: Theory and…

Computational Geometry · Computer Science 2017-12-29 Carlos Alegría-Galicia , Tzolkin Garduño , Carlos Seara , Areli Rosas-Navarrete , Jorge Urrutia

We study the convergence of random function iterations for finding an invariant measure of the corresponding Markov operator. We call the problem of finding such an invariant measure the stochastic fixed point problem. This generalizes…

Optimization and Control · Mathematics 2024-04-16 Neal Hermer , D. Russell Luke , Anja Sturm

The famous pancake theorem states that for every finite set $X$ in the plane, there exist two orthogonal lines that divide $X$ into four equal parts. We propose an algorithm whose running time is linear in the number of points in $X$ and…

Combinatorics · Mathematics 2026-02-03 Alexey Fakhrutdinov , Oleg R. Musin

Given independent normally distributed points A,B,C,D in Euclidean 3-space, let Q denote the plane determined by A,B,C and D^ denote the orthogonal projection of D onto Q. The probability that the tetrahedron ABCD is acute remains…

Probability · Mathematics 2022-03-22 Steven Finch

One can hardly believe that there is still something to be said about cubic equations. To dodge this doubt, we will instead try and say something about Sylvester. He doubtless found a way of solving cubic equations. As mentioned by Rota, it…

History and Overview · Mathematics 2022-02-28 William Y. C. Chen

A set-system $S\subseteq \{0,1\}^n$ is cube-ideal if its convex hull can be described by capacity and generalized set covering inequalities. In this paper, we use combinatorics, convex geometry, and polyhedral theory to give exponential…

Combinatorics · Mathematics 2026-04-21 Ahmad Abdi , Gérard Cornuéjols , Daniel Dadush , Mahsa Dalirrooyfard

In this paper, we present a local information theoretic approach to explicitly learn probabilistic clustering of a discrete random variable. Our formulation yields a convex maximization problem for which it is NP-hard to find the global…

Machine Learning · Computer Science 2018-10-12 David Qiu , Anuran Makur , Lizhong Zheng

We give two simple proofs of a conjecture of Richard Stanley concerning the equidistribution of derangements and alternating permutations with the maximal number of fixed points.

Combinatorics · Mathematics 2007-05-23 Robin Chapman , Lauren K. Williams

If a line cuts randomly two sides of a triangle, the length of the segment determined by the points of intersection is also random. The object of this study, applied to a particular case, is to calculate the probability that the length of…

History and Overview · Mathematics 2016-02-10 Jesús Álvarez Lobo

A new stochastic primal--dual algorithm for solving a composite optimization problem is proposed. It is assumed that all the functions/operators that enter the optimization problem are given as statistical expectations. These expectations…

Optimization and Control · Mathematics 2020-06-23 Pascal Bianchi , Walid Hachem , Adil Salim

Convex hulls are fundamental objects in computational geometry. In moderate dimensions or for large numbers of vertices, computing the convex hull can be impractical due to the computational complexity of convex hull algorithms. In this…

Computational Geometry · Computer Science 2017-06-16 Robert Graham , Adam M. Oberman

We study four-point correlation functions of half-BPS operators of arbitrary weight for all dimensions d=3,4,5,6 where superconformal theories exist. Using harmonic superspace techniques, we derive the superconformal Ward identities for…

High Energy Physics - Theory · Physics 2008-11-26 Francis A. Dolan , Laurent Gallot , Emery Sokatchev

An important problem in analytic and geometric combinatorics is estimating the number of lattice points in a compact convex set in a Euclidean space. Such estimates have numerous applications throughout mathematics. In this note, we exhibit…

Number Theory · Mathematics 2013-08-19 Lenny Fukshansky , Glenn Henshaw

Solutions to the $n$-dimensional Laplace equation which are constant on a central quadric are found. The associated twistor description of the case $n=3$ is used to characterise Gibbons-Hawking metrics with tri-holomorphic $SL(2, \C)$…

Differential Geometry · Mathematics 2009-11-10 Maciej Dunajski

A kind of fixed-point problem in the area of discrete tomography is proposed and investigated. Our chief concern in this paper is the case of square windows in the plane. Dealing with the arrays which are bounded, of polynomial growth, and…

Combinatorics · Mathematics 2014-04-07 Fumio Hazama

The convex hulls of face-vertex incident vectors of 3-face-colorable convex polytopes are computed. It is found that every such convex hull is a $d$-polytope with $d+2$ or $d+3$ vertices. Utilizing Gale transform and Gale diagram, we…

Combinatorics · Mathematics 2021-11-01 Bo Chen , Chen Peng , Yueshan Xiong

The paper proposes a novel hybrid method for solving equilibrium problems and fixed point problems. By constructing specially cutting-halfspaces, in this algorithm, only an optimization program is solved at each iteration without the…

Optimization and Control · Mathematics 2015-10-30 Dang Van Hieu

In this paper, we introduce and study the following problem and its further generalizations: given two finite collections of sets in a normed space, find a ball whose center lies in a given constraint set with the smallest radius that…

Optimization and Control · Mathematics 2012-10-12 Nguyen Mau Nam , Nguyen Hoang

We present a fast and accurate solution to the perspective $n$-points problem, by way of a new approach to the n=4 case. Our solution hinges on a novel separation of variables: given four 3D points and four corresponding 2D points on the…

Algebraic Geometry · Mathematics 2026-02-24 David Lehavi , Brian Osserman