Now showing items 132-151 of 314

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      GA Based Robust Blind Digital Watermarking  [Article]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén; Martín García, Elena; Osuna Lucena, Amparo (Elsevier, 2018)
      A genetic algorithm based robust blind digital watermarking scheme is presented. The experimental results show that our scheme keeps invisibility, security and robustness more likely than other proposals in the literature, ...
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      Generalized binary arrays from quasi-orthogonal cocycles  [Article]

      Armario Sampalo, José Andrés; Flannery, D. L. (Springer, 2019)
      Generalized perfect binary arrays (GPBAs) were used by Jedwab to construct perfect binary arrays. A non-trivial GPBA can exist only if its energy is 2 or a multiple of 4. This paper introduces generalized optimal binary ...
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      Generating binary partial Hadamard matrices  [Article]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Falcón Ganfornina, Raúl Manuel; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén; Osuna Lucena, Amparo (Elsevier, 2019)
      This paper deals with partial binary Hadamard matrices. Although there is a fast simple way to generate about a half (which is the best asymptotic bound known so far, see de Launey (2000) and de Launey and Gordon (2001)) ...
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      Geometric Realization of Möbius Triangulations  [Article]

      Chávez de Diego, María José; Fijavz, Gasper; Márquez Pérez, Alberto; Nakamoto, Atsuhiro; Suárez, Esperanza (2008)
      A Möbius triangulation is a triangulation on the Möbius band. A geometric realization of a map M on a surface $\Sigma$ is an embedding of $\Sigma$ into a Euclidean 3-space $\mathbb{R}^3$ such that each face of M is a flat ...
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      Geometric tree graphs of points in convex position  [Article]

      Hernando, María del Carmen; Hurtado, Ferrán; Márquez Pérez, Alberto; Mora, Mercé; Noy, Marc (1999)
      Given a set P of points in the plane, the geometric tree graph of P is defined as the graph T(P) whose vertices are non-crossing spanning with straight edges trees of P, and where two trees T1 and T2 are adjacent if T2 = ...
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      Geometría del arco carpanel  [Article]

      Encarnación Abajo Casado; Juan Manuel Delgado Sánchez (Federación Española de Profesores de Matemáticas, 2015)
      la fuerza y belleza de las imágenes debería usarse para entender la conexión entre la vida real y las matemáticas. Nos motiva estimular a nuestros alumnos en el análisis de las curvas y superficies de su entorno. En ...
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      Gromov hyperbolicity in strong product graphs  [Article]

      Carballosa, Walter; Moreno Casablanca, Rocío; Cruz, Amauris de la; Rodríguez, José M. (E-JC, 2013)
      If X is a geodesic metric space and x1; x2; x3 2 X, a geodesic triangle T = fx1; x2; x3g is the union of the three geodesics [x1x2], [x2x3] and [x3x1] in X. The space X is -hyperbolic (in the Gromov sense) if any side ...
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      Gröbner bases and cocyclic Hadamard matrices  [Article]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Falcón Ganfornina, Raúl Manuel; Frau García, María Dolores; Gudiel Rodríguez, Félix (Elsevier, 2018)
      Hadamard ideals were introduced in 2006 as a set of nonlin-ear polynomial equations whose zeros are uniquely related toHadamard matrices with one or two circulant cores of a given or-der. Based on this idea, the cocyclic ...
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      Gröbner bases and logarithmic D-modules  [Article]

      Castro Jiménez, Francisco Jesús; Ucha Enríquez, José María (Elsevier, 2006)
      Let C[x] = C[x1, . . . , xn] be the ring of polynomials with complex coefficients and An the Weyl algebra of order n over C. Elements in An are linear differential operators with polynomial coefficients. For each polynomial ...
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      Gröbner bases and the number of Latin squares related to autotopisms of order ≤7  [Article]

      Falcón Ganfornina, Raúl Manuel; Martín Morales, Jorge (Elsevier, 2007)
      Latin squares can be seen as multiplication tables of quasigroups, which are, in general, noncommutativeand non-associative algebraic structures. The number of Latin squares having a fixed isotopismin their autotopism group ...
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      Gymkhana geométrica en el parque de María Luisa  [Presentation]

      Falcón Ganfornina, Raúl Manuel (2008-10)
      El presente taller muestra las posibilidades geométricas que ofrece nuestro entorno inmediato para el desarrollo de actividades matemáticas. En concreto, se pretende que los participantes del presente taller realicen una ...
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      Harmonic mappings and conformal minimal immersions of Riemann surfaces into RN  [Article]

      Alarcón, Antonio; Fernández Delgado, Isabel; López, Francisco J. (Springer, 2013)
      We prove that for any open Riemann surface N, natural number N ≥ 3, non-constant harmonic map h:N→R N−2 and holomorphic 2-form H on N , there exists a weakly complete harmonic map X=(Xj)j=1,…,\scN:N→R\scN with Hopf ...
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      High order extensions of Roe schemes for two dimensional nonconservative hyperbolic systems  [Article]

      Castro Díaz, Manuel Jesús; Fernández Nieto, Enrique Domingo; Ferreiro Ferreiro, Ana María; García Rodríguez, J.A.; Parés Madroñal, Carlos (Plenum Press, 2009)
      This paper is concerned with the development of well-balanced high order Roe methods for two-dimensional nonconservative hyperbolic systems. In particular, we are interested in extending the methods introduced in [3] to ...
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      Homological models for semidirect products of finitely generated Abelian groups  [Article]

      Álvarez Solano, Víctor; Frau García, María Dolores; Real Jurado, Pedro; Armario Sampalo, José Andrés (2012)
      Let G be a semidirect product of finitely generated Abelian groups. We provide a method for constructing an explicit contraction (special homotopy equivalence) from the reduced bar construction of the group ring of G, ...
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      Homological optimality in Discrete Morse Theory through chain homotopies  [Article]

      Molina Abril, Helena; Real Jurado, Pedro (2012)
      Morse theory is a fundamental tool for analyzing the geometry and topology of smooth manifolds. This tool was translated by Forman to discrete structures such as cell complexes, by using discrete Morse functions or ...
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      Homological spanning forest framework for 2D image analysis  [Article]

      Molina Abril, Helena; Real Jurado, Pedro (2012)
      A 2D topology-based digital image processing framework is presented here. This framework consists of the computation of a flexible geometric graph-based structure, starting from a raster representation of a digital image ...
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      Inf-Sup Stable Finite Element Methods for the Landau--Lifshitz--Gilbert and Harmonic Map Heat Flow Equations  [Article]

      Gutiérrez Santacreu, Juan Vicente; Restelli, Marco (SIAM: Society for Industrial and Applied Mathematics, 2017)
      In this paper we propose and analyze a finite element method for both the harmonic map heat and Landau–Lifshitz–Gilbert equation, the time variable remaining continuous. Our starting point is to set out a unified saddle ...
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      Infinite graph embeddings on tubular surfaces  [Article]

      Boza Prieto, Luis; Fedriani Martel, Eugenio Manuel; Márquez Pérez, Alberto; Núñez Valdés, Juan; Revuelta Marchena, María Pastora (2001)
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      Inmersiones condicionadas de grafos en superficies y seudosuperficies  [Article]

      Fedriani Martel, Eugenio Manuel; Boza Prieto, Luis (1999)
      En este traba jo se procede a recapitular resultados conocidos sobre el problema de caracterizar los grafos que admiten inmersiones en super cies y en seudosuper - cies con todos los v ertices en la misma cara y se da ...
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      Integration of a CAS/DGS as a CAD system in the mathematics curriculum for architecture students  [Article]

      Falcón Ganfornina, Raúl Manuel (Taylor & Francis, 2011-09-15)
      Students of Architecture and Building Engineering Degrees work withComputer Aided Design systems daily in order to design and modelarchitectonic constructions. Since this kind of software is based on thecreation and ...