Now showing items 1-20 of 33

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      A genetic algorithm for cocyclic hadamard matrices  [Chapter of Book]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (2006)
      A genetic algorithm for finding cocyclic Hadamard matrices is described. Though we focus on the case of dihedral groups, ...
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      A Mathematica Notebook for Computing the Homology of Iterated Products of Groups  [Chapter of Book]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (2006)
      Let G be a group which admits the structure of an iterated product of central extensions and semidirect products of abelian ...
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      A Mixed Heuristic for Generating Cocyclic 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 (Springer, 2018)
      A way of generating cocyclic Hadamard matrices is described, which combines a new heuristic, coming from a novel notion ...
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      ACS Searching for D4t-Hadamard Matrices  [Presentation]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén; Martín García, Elena; Osuna Lucena, Amparo (Springer, 2010)
      An Ant Colony System (ACS) looking for cocyclic Hadamard matrices over dihedral groups D4t is described. The underlying ...
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      An algorithm for computing cocyclic matrices developed over some semidirect products  [Chapter of Book]

      Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro; Álvarez Solano, Víctor (2001)
      An algorithm for calculating a set ofgenerators ofrepresentative 2-cocycles on semidirect product offinite abelian groups ...
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      Boolean Functions and Permanents of Sylvester Hadamard Matrices  [Article]

      Armario Sampalo, José Andrés (MDPI, 2021-01-17)
      One of the fastest known general techniques for computing permanents is Ryser’s formula. On this note, we show that this ...
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      Calculating cocyclic hadamard matrices in Mathematica: exhaustive and heuristic searches  [Chapter of Book]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (2006)
      We describe a notebook in Mathematica which, taking as input data a homological model for a finite group G of order |G| = ...
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      Comparison maps for relatively free resolutions  [Chapter of Book]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (2006)
      Let Λ be a commutative ring, A an augmented differential graded algebra over Λ (briefly, DGA-algebra) and X be a relatively ...
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      Computing “Small” 1–Homological Models for Commutative Differential Graded Algebras  [Presentation]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; González Díaz, Rocío; Jiménez Rodríguez, María José; Real Jurado, Pedro; Silva Gallardo, Beatriz (Springer, 2000)
      We use homological perturbation machinery specific for the algebra category [13] to give an algorithm for computing the ...
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      Determinants of (–1,1)-matrices of the skew-symmetric type: a cocyclic approach  [Article]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix (Walter de Gruyter GmbH, 2015)
      An n by n skew-symmetric type (−1, 1)-matrix K = [ki,j ] has 1’s on the main diagonal and ±1’s elsewhere with ki,j = ...
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      Embedding cocylic D-optimal designs in cocylic Hadamard matrices  [Article]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix (International Linear Algebra Society, 2012)
      A method for embedding cocyclic submatrices with “large” determinants of orders 2t in certain cocyclic Hadamard matrices ...
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      Error correcting codes from quasi-Hadamard matrices  [Presentation]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Martín García, Elena; Osuna Lucena, Amparo (Springer, 2007)
      Levenshtein described in [5] a method for constructing error correcting codes which meet the Plotkin bounds, provided ...
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      Estructuras multiplicativas y homología de fibrados  [PhD Thesis]

      Armario Sampalo, José Andrés (1999)
      Como es bien conocido, los principales mecanismos algebraicos para obtener información homológica de los espacios fibrados ...
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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 ...
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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 ...
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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 ...
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      Generating partial Hadamard matrices as solutions to a Constraint Satisfaction Problem characterizing cliques  [Presentation]

      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 (2017-07)
      A procedure is described looking for partial Hadamard matrices, as cliques of a particular subgraph Gt of Ito’s Hadamard ...
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      Gröbner bases and cocyclic Hadamard matrices  [Presentation]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Falcón Ganfornina, Raúl Manuel; Frau García, María Dolores; Gudiel Rodríguez, Félix (2017-07)
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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 ...
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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 ...