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Related papers: Geometric Separability using Orthogonal Objects

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In this work, we carry out structural and algorithmic studies of a problem of barrier forming: selecting theminimum number of straight line segments (barriers) that separate several sets of mutually disjoint objects in the plane. The…

Robotics · Computer Science 2022-02-25 Si Wei Feng , Jingjin Yu

We propose a novel abstraction of the image segmentation task in the form of a combinatorial optimization problem that we call the multi-separator problem. Feasible solutions indicate for every pixel whether it belongs to a segment or a…

Computer Vision and Pattern Recognition · Computer Science 2023-07-11 Jannik Irmai , Shengxian Zhao , Jannik Presberger , Bjoern Andres

The reachability problem asks to decide if there exists a path from one vertex to another in a digraph. In a grid digraph, the vertices are the points of a two-dimensional square grid, and an edge can occur between a vertex and its…

Computational Complexity · Computer Science 2025-01-03 Rahul Jain , Raghunath Tewari

Let $\D$ be a set of $n$ pairwise disjoint unit balls in $\R^d$ and $P$ the set of their center points. A hyperplane $\Hy$ is an \emph{$m$-separator} for $\D$ if each closed halfspace bounded by $\Hy$ contains at least $m$ points from $P$.…

Computational Geometry · Computer Science 2014-05-09 Michael Hoffmann , Vincent Kusters , Tillmann Miltzow

Benjamini and Papasoglou (2011) showed that planar graphs with uniform polynomial volume growth admit $1$-dimensional annular separators: The vertices at graph distance $R$ from any vertex can be separated from those at distance $2R$ by…

Combinatorics · Mathematics 2021-07-22 Farzam Ebrahimnejad , James R. Lee

The paper considers the minimization of a separable convex function subject to linear ascending constraints. The problem arises as the core optimization in several resource allocation scenarios, and is a special case of an optimization of a…

Optimization and Control · Mathematics 2016-08-30 Akhil P T , Rajesh Sundaresan

The {\sc $c$-Balanced Separator} problem is a graph-partitioning problem in which given a graph $G$, one aims to find a cut of minimum size such that both the sides of the cut have at least $cn$ vertices. In this paper, we present new…

Data Structures and Algorithms · Computer Science 2010-11-22 Manjish Pal

Geometric programming problem is a powerful tool for solving some special type non-linear programming problems. It has a wide range of applications in optimization and engineering for solving some complex optimization problems. Many…

Data Structures and Algorithms · Computer Science 2010-03-25 A. K. Ojha , K. K. Biswal

The (unweighted) point-separation problem asks, given a pair of points $s$ and $t$ in the plane, and a set of candidate geometric objects, for the minimum-size subset of objects whose union blocks all paths from $s$ to $t$. Recent work has…

Computational Geometry · Computer Science 2026-02-16 Jayson Lynch , Jack Spalding-Jamieson

In this article, we consider a collection of geometric problems involving points colored by two colors (red and blue), referred to as bichromatic problems. The motivation behind studying these problems is two fold; (i) these problems appear…

Computational Geometry · Computer Science 2016-10-04 Sayan Bandyapadhyay , Aritra Banik

Let $G$ be a graph and $a,b$ vertices of $G$. A minimal $a,b$-separator of $G$ is an inclusion-wise minimal vertex set of $G$ that separates $a$ and $b$. We consider the problem of enumerating the minimal $a,b$-separators of $G$ that…

Data Structures and Algorithms · Computer Science 2020-12-17 Tuukka Korhonen

In an undirected connected graph G=(V,E), the vertex separator problem (VSP) asks for a partition of V into nonempty subsets A, B, C such that |C| is minimized such that there is no edge between A and B, and sizes of A and B are similar.…

Discrete Mathematics · Computer Science 2007-11-21 Marie-Jean Meurs

We present a rectangle-based segmentation algorithm that sets up a graph and performs a graph cut to separate an object from the background. However, graph-based algorithms distribute the graph's nodes uniformly and equidistantly on the…

Computer Vision and Pattern Recognition · Computer Science 2012-03-14 Jan Egger , Tina Kapur , Thomas Dukatz , Malgorzata Kolodziej , Dzenan Zukic , Bernd Freisleben , Christopher Nimsky

Suppose we are given a pair of points $s, t$ and a set $S$ of $n$ geometric objects in the plane, called obstacles. We show that in polynomial time one can construct an auxiliary (multi-)graph $G$ with vertex set $S$ and every edge labeled…

Computational Geometry · Computer Science 2022-03-17 Neeraj Kumar , Daniel Lokshtanov , Saket Saurabh , Subhash Suri , Jie Xue

We propose a new approach to the combinatorial interpretations of linearization coefficient problem of orthogonal polynomials. We first establish a difference system and then solve it combinatorially and analytically using the method of…

Classical Analysis and ODEs · Mathematics 2012-11-20 Mourad E. H. Ismail , Anisse Kasraoui , Jiang Zeng

Motivated by an intention to apply partial wave analysis to systems containing photons, we construct eigenvectors of the distance of separation between two photons. A choice is made that makes the case of two photons most closely resemble…

Quantum Physics · Physics 2021-08-17 Scott E. Hoffmann

The Separation of Variables theory for the Hamilton-Jacobi equation is 'by definition' related to the use of special kinds of coordinates, for example Jacobi coordinates on the ellipsoid or St\"ackel systems in the Euclidean space. However,…

Mathematical Physics · Physics 2009-07-20 Giovanni Rastelli

This paper present a geometric diagram of a separable state: If a mixed state $\sigma $ is separable, there are $2^{nS(\sigma)}$ linearly independant product vectors which span the same Hilbert space as the $2^{nS(\sigma)}$ ``likely''…

Quantum Physics · Physics 2007-05-23 Ping Xing Chen , Cheng Zu Li

The practically useful criteria of separable states $\rho=\sum_{k}w_{k}\rho_{k}$ in $d=2\times2$ are discussed. The equality $G({\bf a},{\bf b})= 4[\langle \psi|P({\bf a})\otimes P({\bf b})|\psi\rangle-\langle \psi|P({\bf a})\otimes{\bf…

Quantum Physics · Physics 2016-04-20 Kazuo Fujikawa , C. H. Oh , Koichiro Umetsu , Sixia Yu

We study the problem of partitioning a given simple polygon $P$ into a minimum number of connected polygonal pieces, each of bounded size. We describe a general technique for constructing such partitions that works for several notions of…

Computational Geometry · Computer Science 2024-10-23 Mikkel Abrahamsen , Nichlas Langhoff Rasmussen