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Recently, Yeh [Yeh, WC. (2006). A simple algorithm to search for all MCs in networks. European Journal of Operational Research, 174, 1694{1705.] has proposed a simple algorithm to find all the Minimal Cuts in an undirected graph. However,…

Optimization and Control · Mathematics 2014-01-03 Majid Forghani-elahabad , Nezam Mahdavi-Amiri

Stratified digraphs are popular models for feedforward neural networks. However, computation of their path homologies has been limited to low dimensions due to high computational complexity. A recursive algorithm is proposed to compute…

Computational Geometry · Computer Science 2024-12-12 Zhengtong Zhu , Zhiyi Chi

A polynomial algorithm for graphs' isomorphism testing is constructed in assumption that there exists a corresponding polynomial algorithm for graphs with trivial automorphism group.

Combinatorics · Mathematics 2007-05-23 Aleksandr Golubchik

We propose an effective algorithm that enumerates (and actually finds) all 3-edge colorings and Hamiltonian cycles in a cubic graph. The idea is to make a preliminary run that separates the vertices into two types: ``rigid'' (such that the…

Combinatorics · Mathematics 2009-09-29 V. Ejov , N. Pugacheva , S. Rossomakhine , P. Zograf

We present a new formula for the coaction of a large class of integrals. When applied to one-loop (cut) Feynman integrals, it can be given a diagrammatic representation purely in terms of pinches and cuts of the edges of the graph. The…

High Energy Physics - Theory · Physics 2018-03-16 Samuel Abreu , Ruth Britto , Claude Duhr , Einan Gardi

A graph drawn in a surface is a near-quadrangulation if the sum of the lengths of the faces different from 4-faces is bounded by a fixed constant. We leverage duality between colorings and flows to design an efficient algorithm for…

Combinatorics · Mathematics 2023-03-13 Caroline Bang , Zdeněk Dvořák , Emily Heath , Bernard Lidický

Bestvina and Handel have found an effective algorithm that determines whether a given homeomorphism of an orientable, possibly punctured surface is pseudo-Anosov. We present a software package in Java that realizes this algorithm for…

Group Theory · Mathematics 2007-05-23 Peter Brinkmann

We develop a theory of confluence of graphs. We describe an algorithm for proving that a given system of reduction rules for abstract graphs and graphs in surfaces is locally confluent. We apply this algorithm to show that each simple Lie…

Quantum Algebra · Mathematics 2014-10-01 Adam S. Sikora , Bruce W. Westbury

The main purpose of this paper is to lay the foundations of a general theory which encompasses the features of the classical Hough transform and extend them to general algebraic objects such as affine schemes. The main motivation comes from…

Commutative Algebra · Mathematics 2012-02-09 Mauro C. Beltrametti , Lorenzo Robbiano

To any generic curve in an oriented surface there corresponds an oriented chord diagram, and any oriented chord diagram may be realized by a curve in some oriented surface. The genus of an oriented chord diagram is the minimal genus of an…

Geometric Topology · Mathematics 2009-04-29 Nathan Linial , Tahl Nowik

We present a simple $(1+\varepsilon)\Delta$-edge-coloring algorithm for graphs of maximum degree $\Delta = \Omega(\log n / \varepsilon)$ with running time $O\left(m\,\log^3 n/\varepsilon^3\right)$. Our algorithm improves upon that of [Duan,…

Data Structures and Algorithms · Computer Science 2024-07-24 Abhishek Dhawan

The method of Symmetries of Feynman Integrals defines for any Feynman diagram a set of partial differential equations. On some locus in parameter space the equations imply that the diagram can be reduced to a linear combination of simpler…

High Energy Physics - Theory · Physics 2018-04-05 Barak Kol

A previously proposed two-step algorithm for calculating the expectation values of Chern-Simons graphs fails to determine certain crucial signs. The step which involves calculating tetrahedra by solving certain non- linear equations is…

High Energy Physics - Theory · Physics 2009-10-22 Stephen G. Naculich , Harold A. Riggs , Howard J. Schnitzer

The class of closed graphs by a linear ordering on their sets of vertices is investigated. A recent characterization of such a class of graphs is analyzed by using tools from the proper interval graph theory.

Combinatorics · Mathematics 2015-09-23 Marilena Crupi

Finding surface mappings with least distortion arises from many applications in various fields. Extremal Teichm\"uller maps are surface mappings with least conformality distortion. The existence and uniqueness of the extremal…

Differential Geometry · Mathematics 2013-07-11 Lui Lok Ming , Gu Xianfeng , Yau Shing-Tung

Using vertex algebra techniques, we determine a set of generators for the cohomology ring of the Hilbert schemes of points on an arbitrary smooth projective surface over the field of complex numbers.

Algebraic Geometry · Mathematics 2007-05-23 Wei-ping Li , Zhenbo Qin , Weiqiang Wang

We provide a simple and efficient algorithm for computing the Euclidean projection of a point onto the capped simplex---a simplex with an additional uniform bound on each coordinate---together with an elementary proof. Both the MATLAB and…

Machine Learning · Computer Science 2015-03-04 Weiran Wang , Canyi Lu

Surface parameterization is widely used in computer graphics and geometry processing. It simplifies challenging tasks such as surface registrations, morphing, remeshing and texture mapping. In this paper, we present an efficient algorithm…

Computational Geometry · Computer Science 2020-02-10 Gary Pui-Tung Choi , Lok Ming Lui

We present an algorithm that covers any given rational ruled surface with two rational parametrizations. In addition, we present an algorithm that transforms any rational surface parametrization into a new rational surface parametrization…

Algebraic Geometry · Mathematics 2014-10-08 J. Rafael Sendra , David Sevilla , Carlos Villarino

We give polynomial-time algorithms for obtaining hamilton circuits in random graphs, G, and random directed graphs, D. If n is finite, we assume that G or D contains a hamilton circuit. If G is an arbitrary graph containing a hamilton…

Combinatorics · Mathematics 2007-05-23 Howard Kleiman