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We study the following variant of the 15 puzzle. Given a graph and two token placements on the vertices, we want to find a walk of the minimum length (if any exists) such that the sequence of token swappings along the walk obtains one of…

Data Structures and Algorithms · Computer Science 2025-07-30 Hironori Kiya , Yuto Okada , Hirotaka Ono , Yota Otachi

Various topological indices, based on the distances between the vertices of a graph, are widely used in theoretical chemistry. The degree resistance distance of a graph $G$ is defined as ${D_R}(G) = \sum\limits_{\{u,v\} \subseteq V(G)}…

Combinatorics · Mathematics 2016-04-19 Jia-Bao Liu , Xiang-Feng Pan

We determine the Waring ranks of all sextic binary forms with complex coefficients using a Geometric Invariant Theory approach. Using the five basic invariants for sextic binary forms, our results give a rapid method to determine the Waring…

Algebraic Geometry · Mathematics 2022-08-10 Alexandru Dimca , Gabriel Sticlaru

Let $\nu$ be a vector measure defined on a $\sigma$-algebra $\Sigma$ and taking values in a Banach space. We prove that if $\nu$ is homogeneous and $L_1(\nu)$ is non-separable, then there is a vector measure $\tilde{\nu}:\Sigma \to…

Functional Analysis · Mathematics 2024-04-09 José Rodríguez

We study the local differential geometry of varieties $X^n\subset \Bbb C\Bbb P^{n+a}$ with degenerate secant and tangential varieties. We show that the second fundamental form of a smooth variety with degenerate tangential variety is…

alg-geom · Mathematics 2008-02-03 J. M. Landsberg

Under certain effective positivity conditions, we show that the secant variety to a smooth variety satisfies $N_{3,p}$. For smooth curves, we provide the best possible effective bound on the degree $d$ of the embedding, $d\geq 2g+3+p$.

Algebraic Geometry · Mathematics 2009-08-04 Peter Vermeire

We generalize the classical Terracini's Lemma to higher order osculating spaces to secant varieties. As an application, we address with the so-called Horace method the case of the $d$-Veronese embedding of the projective 3-space.

Algebraic Geometry · Mathematics 2007-05-23 E. Ballico , C. Bocci , E. Carlini , C. Fontanari

A capsule is a group of neurons whose activity vector models different properties of the same entity. This paper extends the capsule to a generative version, named variational capsules (VCs). Each VC produces a latent variable for a…

Computer Vision and Pattern Recognition · Computer Science 2018-07-12 Huaibo Huang , Lingxiao Song , Ran He , Zhenan Sun , Tieniu Tan

The Chow form of the essential variety in computer vision is calculated. Our derivation uses secant varieties, Ulrich sheaves and representation theory. Numerical experiments show that our formula can detect noisy point correspondences…

Algebraic Geometry · Mathematics 2016-07-15 Gunnar Fløystad , Joe Kileel , Giorgio Ottaviani

The Wiener polarity index of a graph G is the number of unordered pairs of vertices u, v such that the distance between u and v is 3. In this paper we give an explicit formula for the Wiener polarity index of cactus graphs. We also deduce…

Combinatorics · Mathematics 2014-09-19 Nan Chen , Wen-Xue Du , Yi-Zheng Fan

The classical decision problem, as it is understood today, is the quest for a delineation between the decidable and the undecidable parts of first-order logic based on elegant syntactic criteria. In this paper, we treat the concept of…

Logic in Computer Science · Computer Science 2019-11-27 Marco Voigt

Let $X\subset \P^N$ be a nondegenerate irreducible closed subvariety of dimension $n$ over the field of complex numbers and let $SX\subset\P^N$ be its secant variety. $X\subset\P^N$ is called `secant defective' if $\dim(SX)$ is strictly…

Algebraic Geometry · Mathematics 2024-04-30 Kangjin Han

This article studies the Minimum Spanning Tree Problem under Explorable Uncertainty as well as a related vertex uncertainty version of the problem. We particularly consider special instance types, including cactus graphs, for which we…

Data Structures and Algorithms · Computer Science 2022-11-29 Corinna Mathwieser , Eranda Cela

It is shown how piecewise differentiable functions $F: \mathbb R^n \mapsto \mathbb R^m $ that are defined by evaluation programs can be approximated locally by a piecewise linear model based on a pair of sample points $\check x$ and $\hat…

Numerical Analysis · Mathematics 2017-08-14 Andreas Griewank , Tom Streubel , Lutz Lehmann , Manuel Radons , Richard Hasenfelder

Simplified vine copulas (SVCs), or pair-copula constructions, have become an important tool in high-dimensional dependence modeling. So far, specification and estimation of SVCs has been conducted under the simplifying assumption, i.e., all…

Methodology · Statistics 2021-01-11 Fabian Spanhel , Malte S. Kurz

Support vector machines (SVM) and other kernel techniques represent a family of powerful statistical classification methods with high accuracy and broad applicability. Because they use all or a significant portion of the training data,…

Machine Learning · Statistics 2023-01-31 Peter Mills

Plants are fundamentally important to life. Key research areas in plant science include plant species identification, weed classification using hyper spectral images, monitoring plant health and tracing leaf growth, and the semantic…

Computer Vision and Pattern Recognition · Computer Science 2020-09-15 K. K. Thyagharajan , I. Kiruba Raji

We prove (with a mild restriction on the multidegrees) that all secant varieties of Segre-Veronese varieties with $k>2$ factors, $k-2$ of them being $\mathbb{P}^1$, have the expected dimension. This is equivalent to compute the dimension of…

Algebraic Geometry · Mathematics 2023-06-12 Edoardo Ballico

This paper is devoted to the study of the separability problem in the field of Quantum information theory. We deal mainly with the bipartite finite dimensional case and with two types of matrices, one of them being the PPT matrices. We…

Quantum Physics · Physics 2016-03-21 Daniel Cariello

Let $\nu_d : \mathbb{P}^n \longrightarrow \mathbb{P}^N$ be the Veronese mapping of degree $d$ where $N = {n+d \choose n} -1$. By an elementary approach it is shown that $\nu_d$ is an isomorphism of $\mathbb{P}^n$ onto the projective variety…

Algebraic Geometry · Mathematics 2023-11-07 Rahim Zaare-Nahandi