Data

NameArmario Sampalo, José Andrés
DepartmentMatemática Aplicada I
Knowledge areaMatemática Aplicada
Professional categoryProfesor Titular de Universidad
E-mailRequest
           

  Statistics

  • Items

    33

  • Visits

    1852

  • Downloads

    1657

  Publications

 

Article
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Boolean Functions and Permanents of Sylvester Hadamard Matrices

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 ...
Article
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On Cocyclic Hadamard Matrices over Goethals-Seidel Loops

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 (MDPI, 2020-01-01)
About twenty-five years ago, Horadam and de Launey introduced the cocyclic development of designs, from which the notion ...
Article
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Generating binary partial Hadamard matrices

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, 2019-01-01)
This paper deals with partial binary Hadamard matrices. Although there is a fast simple way to generate about a half (which ...
Article
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Generalized binary arrays from quasi-orthogonal cocycles

Armario Sampalo, José Andrés; Flannery, D. L. (Springer, 2019-01-01)
Generalized perfect binary arrays (GPBAs) were used by Jedwab to construct perfect binary arrays. A non-trivial GPBA can ...
Article
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Quasi-Hadamard Full Propelinear Codes

Armario Sampalo, José Andrés; Bailera, Iván; Borges, Joachim; Rifá, Josep (Springer, 2018-01-01)
In this paper, we give a characterization of quasi-Hadamard groups in terms of propelinear codes. We define a new class ...
Article
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A Mixed Heuristic for Generating Cocyclic Hadamard Matrices

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, 2018-01-01)
A way of generating cocyclic Hadamard matrices is described, which combines a new heuristic, coming from a novel notion ...
Article
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GA Based Robust Blind Digital Watermarking

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, 2018-01-01)
A genetic algorithm based robust blind digital watermarking scheme is presented. The experimental results show that our ...
Article
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Gröbner bases and cocyclic Hadamard matrices

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Falcón Ganfornina, Raúl Manuel; Frau García, María Dolores; Gudiel Rodríguez, Félix (Elsevier, 2018-01-01)
Hadamard ideals were introduced in 2006 as a set of nonlin-ear polynomial equations whose zeros are uniquely related ...
Presentation
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Gröbner bases and cocyclic Hadamard matrices

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Falcón Ganfornina, Raúl Manuel; Frau García, María Dolores; Gudiel Rodríguez, Félix (2017-07-01)
Presentation
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Generating partial Hadamard matrices as solutions to a Constraint Satisfaction Problem characterizing cliques

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 (2017-07-01)
A procedure is described looking for partial Hadamard matrices, as cliques of a particular subgraph Gt of Ito’s Hadamard ...
Presentation
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(Pseudo)-cocyclic (structured) Hadamard matrices over (quasi)groups

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Falcón Ganfornina, Raúl Manuel; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén; Kotsireas, Ilias (2017-01-01)
Progressing on a survey of the state of the art of cocyclic constructions for Hadamard matrices, we will prove that the ...
Article
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On quasi-orthogonal cocycles

Armario Sampalo, José Andrés; Flannery, D.L. (Wiley, 2017-01-01)
We introduce the notion of quasi-orthogonal cocycle. This is motivated in part by the maximal determinant problem for ...
Article
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On higher dimensional cocyclic Hadamard matrices

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (2015-01-01)
Provided that a cohomological model for G is known, we describe a method for constructing a basis for n-cocycles over G, ...
Article
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Determinants of (–1,1)-matrices of the skew-symmetric type: a cocyclic approach

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix (Walter de Gruyter GmbH, 2015-01-01)
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 = −kj,i. ...
Article
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Self-Dual codes from (−1,1)-matrices of skew symmetric type

Armario Sampalo, José Andrés; Frau García, María Dolores (Cornell University, 2013-01-01)
Previously, self-dual codes have been constructed from weighing matrices, and in particular from conference matrices (skew ...
Article
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Homological models for semidirect products of finitely generated Abelian groups

Álvarez Solano, Víctor; Frau García, María Dolores; Real Jurado, Pedro; Armario Sampalo, José Andrés (2012-01-01)
Let G be a semidirect product of finitely generated Abelian groups. We provide a method for constructing an explicit ...
Article
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Embedding cocylic D-optimal designs in cocylic Hadamard matrices

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix (International Linear Algebra Society, 2012-01-01)
A method for embedding cocyclic submatrices with “large” determinants of orders 2t in certain cocyclic Hadamard matrices ...
Presentation
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Project Estimation with NDT

Armario Sampalo, José Andrés; Gutiérrez Rodríguez, Javier Jesús; Alba Ortega, Manuel; García García, Julián Alberto; Vitorio, J.; Escalona Cuaresma, María José (ScitePress Digital Library, 2012-01-01)
Software Project Estimation is one of the most critical and complex task for a Project manager. Several techniques, tools ...
Presentation
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Searching for partial Hadamard matrices

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén; Martín García, Elena; Osuna Lucena, Amparo (Universidade de Santiago de Compostela, Servicio de Publicaciones, 2010-01-01)
Three algorithms looking for pretty large partial Hadamard ma- trices are described. Here “large” means that hopefully ...
Article
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On an inequivalence criterion for cocyclic Hadamard matrices

Armario Sampalo, José Andrés (Springer, 2010-01-01)
Given two Hadamard matrices of the same order, it can be quite difficult to decide whether or not they are equivalent. ...
Presentation
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ACS Searching for D4t-Hadamard Matrices

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, 2010-01-01)
An Ant Colony System (ACS) looking for cocyclic Hadamard matrices over dihedral groups D4t is described. The underlying ...
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The homological reduction method for computing cocyclic Hadamard matrices

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (2009-01-01)
An alternate method for constructing (Hadamard) cocyclic matrices over a finite group GG is described. Provided that a ...
Presentation
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Rooted Trees Searching for Cocyclic Hadamard Matrices over D4t

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix; Osuna Lucena, Amparo (Springer, 2009-01-01)
A new reduction on the size of the search space for cocyclic Hadamard matrices over dihedral groups D4t is described, in ...
Presentation
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Error correcting codes from quasi-Hadamard matrices

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Martín García, Elena; Osuna Lucena, Amparo (Springer, 2007-01-01)
Levenshtein described in [5] a method for constructing error correcting codes which meet the Plotkin bounds, provided ...
Chapter of Book
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A genetic algorithm for cocyclic hadamard matrices

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (2006-01-01)
A genetic algorithm for finding cocyclic Hadamard matrices is described. Though we focus on the case of dihedral groups, ...
Chapter of Book
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Comparison maps for relatively free resolutions

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (2006-01-01)
Let Λ be a commutative ring, A an augmented differential graded algebra over Λ (briefly, DGA-algebra) and X be a relatively ...
Chapter of Book
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A Mathematica Notebook for Computing the Homology of Iterated Products of Groups

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (2006-01-01)
Let G be a group which admits the structure of an iterated product of central extensions and semidirect products of abelian ...
Chapter of Book
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Calculating cocyclic hadamard matrices in Mathematica: exhaustive and heuristic searches

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (2006-01-01)
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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Transferring TTP-structures via contraction

Frau García, María Dolores; Real Jurado, Pedro; Armario Sampalo, José Andrés; Álvarez Solano, Víctor (2005-01-01)
Presentation
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Matrices cocíclicas de Hadamard sobre productos semidirectos

Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (Alberto Márquez, 2002-01-01)
Chapter of Book
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An algorithm for computing cocyclic matrices developed over some semidirect products

Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro; Álvarez Solano, Víctor (2001-01-01)
An algorithm for calculating a set ofgenerators ofrepresentative 2-cocycles on semidirect product offinite abelian groups ...
Presentation
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Computing “Small” 1–Homological Models for Commutative Differential Graded Algebras

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, 2000-01-01)
We use homological perturbation machinery specific for the algebra category [13] to give an algorithm for computing the ...
PhD Thesis
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Estructuras multiplicativas y homología de fibrados

Real Jurado, Pedro; Armario Sampalo, José Andrés (1999-01-01)
Como es bien conocido, los principales mecanismos algebraicos para obtener información homológica de los espacios fibrados ...