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Computational models of complex physical systems often rely on simplifying assumptions which inevitably introduce model error, with consequent predictive errors. Given data on model observables, the estimation of parameterized model-error…

Methodology · Statistics 2026-02-23 Mridula Kuppa , Khachik Sargsyan , Marco Panesi , Habib N. Najm

We propose an approach for capturing the signal variability in hyperspectral imagery using the framework of the Grassmann manifold. Labeled points from each class are sampled and used to form abstract points on the Grassmannian. The…

Computer Vision and Pattern Recognition · Computer Science 2015-02-04 Sofya Chepushtanova , Michael Kirby

The aim of this article is to give lower bounds on the parameters of algebraic geometric error-correcting codes constructed from projective bundles over Deligne--Lusztig surfaces. The methods based on an intensive use of the intersection…

Information Theory · Computer Science 2024-01-23 Daniel Camazón Portela , Juan Antonio López Ramos

We introduce a method to produce bounds for the non secant defectivity of an arbitrary irreducible projective variety, once we know how its osculating spaces behave in families and when the linear projections from them are generically…

Algebraic Geometry · Mathematics 2016-10-31 Alex Massarenti , Rick Rischter

Let $n,k$ denote integers with $n>2k\geq 6$. Let $\mathbb{F}_q$ denote a finite field with $q$ elements, and let $V$ denote a vector space over $\mathbb{F}_q$ that has dimension $n$. The projective geometry $P_q(n)$ is the partially ordered…

Combinatorics · Mathematics 2024-08-02 Ian Seong

The Grassmannians of lines in projective N-space, G(1,N), are embedded by way of the Pl"ucker embedding in the projective space P(\bigwedge^2 C^{N+1}). Let H^l be a general l-codimensional linear subspace in this projective space. We…

Algebraic Geometry · Mathematics 2007-05-23 J. Piontkowski , A. Van de Ven

We present a Bayesian approach to identify optimal transformations that map model input points to low dimensional latent variables. The "projection" mapping consists of an orthonormal matrix that is considered a priori unknown and needs to…

Machine Learning · Statistics 2021-09-22 Panagiotis Tsilifis , Piyush Pandita , Sayan Ghosh , Valeria Andreoli , Thomas Vandeputte , Liping Wang

Let $\Gamma_k(V)$ be the Grassmann graph whose vertex set ${\mathcal G}_{k}(V)$ is formed by all $k$-dimensional subspaces of an $n$-dimensional vector space $V$ over the finite field $F_q$ consisting of $q$ elements. Denote by $\Pi[n,k]_q$…

Combinatorics · Mathematics 2025-09-23 Edyta Bartnicka

In this paper, weighted Bergman spaces on the unit ball in C^n are investigated. A characterization of the Carleson embeddings is established. Pointwise and norm estimates on the reproducing kernel function of weighted Bergman spaces on the…

Complex Variables · Mathematics 2026-05-26 Nihat Gökhan Göğüş , Sinem Yelda Sönmez

In this paper, we show how to expand Euclidean/Hermitian self-orthogonal code preserving their orthogonal property. Our results show that every $k$-dimension Hermitian self-orthogonal code is contained in a $(k+1)$-dimensional Hermitian…

Information Theory · Computer Science 2025-11-25 Jon-Lark Kim , Hongwei Liu , Jinquan Luo

We consider linear error correcting codes associated to higher dimensional projective varieties defined over a finite field. The problem of determining the basic parameters of such codes often leads to some interesting and difficult…

Combinatorics · Mathematics 2007-05-23 Sudhir R. Ghorpade , Michael A. Tsfasman

Grassmann tensors arise from classical problems of scene reconstruction in computer vision. Trifocal Grassmann tensors, related to three projections from a projective space of dimension k onto view-spaces of varying dimensions are studied…

Algebraic Geometry · Mathematics 2019-07-25 Marina Bertolini , Gian Mario Besana , Gilberto Bini , Cristina Turrini

We construct Grassmann spaces associated with the incidence geometry of regular and tangential subspaces of a symplectic copolar space, show that the underlying metric projective space can be recovered in terms of the corresponding…

Combinatorics · Mathematics 2012-03-16 M. Prażmowska , K. Prażmowski , M. Żynel

Restricted secant varieties of Grassmannians are constructed from sums of points corresponding to $k$-planes with the restriction that their intersection has a prescribed dimension. We study dimensions of restricted secant of Grassmannians…

Algebraic Geometry · Mathematics 2023-12-06 Dalton Bidleman , Luke Oeding

Grassmannian $\mathcal{G}_q(n,k)$ is the set of all $k$-dimensional subspaces of the vector space $\mathbb{F}_q^n.$ Recently, Etzion and Zhang introduced a new notion called covering Grassmannian code which can be used in network coding…

Information Theory · Computer Science 2022-07-20 Bingchen Qian , Xin Wang , Chengfei Xie , Gennian Ge

Several new constructions of 3-dimensional optical orthogonal codes are presented here. In each case the codes have ideal autocorrelation $\mathbf{ \lambda_a=0} $, and in all but one case a cross correlation of $ \mathbf{\lambda_c=1} $. All…

Information Theory · Computer Science 2022-07-18 Tim L. Alderson

We show that finding orthogonal grid-embeddings of plane graphs (planar with fixed combinatorial embedding) with the minimum number of bends in the so-called Kandinsky model (which allows vertices of degree $> 4$) is NP-complete, thus…

Computational Geometry · Computer Science 2014-05-12 Thomas Bläsius , Guido Brückner , Ignaz Rutter

In this paper, we analyze embeddings of grid graphs on orientable surfaces. We determine the genus of a large class of k-dimensional grid graphs and effective two-sided bounds for the genus of any 3-dimensional grid graph, both in terms of…

Combinatorics · Mathematics 2022-04-20 Christian Millichap , Fabian Salinas

There are two widely used models for the Grassmannian $\operatorname{Gr}(k,n)$, as the set of equivalence classes of orthogonal matrices $\operatorname{O}(n)/(\operatorname{O}(k) \times \operatorname{O}(n-k))$, and as the set of trace-$k$…

Optimization and Control · Mathematics 2020-09-29 Zehua Lai , Lek-Heng Lim , Ke Ye

We introduce the class of transparent embeddings for a point-line geometry $\Gamma = ({\mathcal P},{\mathcal L})$ as the class of full projective embeddings $\varepsilon$ of $\Gamma$ such that the preimage of any projective line fully…

Algebraic Geometry · Mathematics 2018-04-11 Ilaria Cardinali , Luca Giuzzi , Antonio Pasini