• Artículo
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      A computational approach to analyze the Hadamard quasigroup product 

      Falcón Ganfornina, Raúl Manuel; Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén (American Institute of Mathematical Sciences (AIMS), 2023-03-30)
      Based on the binary product described by any Latin square, the Hadamard quasigroup product is introduced in this paper as ...
    • Artículo
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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)
      A way of generating cocyclic Hadamard matrices is described, which combines a new heuristic, coming from a novel notion ...
    • Ponencia
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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)
      An Ant Colony System (ACS) looking for cocyclic Hadamard matrices over dihedral groups D4t is described. The underlying ...
    • Artículo
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      Cocyclic Hadamard matrices over Latin rectangles 

      Álvarez Solano, Víctor; Falcón Ganfornina, Raúl Manuel; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén (Elsevier, 2019)
      In the literature, the theory of cocyclic Hadamard matrices has always been developed over finite groups. This paper ...
    • Ponencia
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      Cocyclic Hadamard matrices over Latin rectangles 

      Falcón Ganfornina, Raúl Manuel; Frau García, María Dolores; Güemes Alzaga, María Belén; Gudiel Rodríguez, Félix; Álvarez Solano, Víctor (2017)
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      Equivalences of Zt×Z22-cocyclic Hadamard matrices 

      Álvarez Solano, Víctor; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén; Horadam, K.J.; Rao, A. (Cornell University, 2015)
      One of the most promising structural approaches to resolving the Hadamard Conjecture uses the family of cocyclic matrices ...
    • Artículo
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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)
      A genetic algorithm based robust blind digital watermarking scheme is presented. The experimental results show that our ...
    • Artículo
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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)
      This paper deals with partial binary Hadamard matrices. Although there is a fast simple way to generate about a half ...
    • Ponencia
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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)
      A procedure is described looking for partial Hadamard matrices, as cliques of a particular subgraph Gt of Ito’s Hadamard ...
    • Artículo
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      Hadamard Matrices with Cocyclic Core 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén; Osuna Lucena, Amparo (MDPI, 2021)
      Since Horadam and de Launey introduced the cocyclic framework on combinatorial designs in the 1990s, it has revealed ...
    • Tesis Doctoral
    • Artículo
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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)
      About twenty-five years ago, Horadam and de Launey introduced the cocyclic development of designs, from which the notion ...
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      On D4t-Cocyclic Hadamard Matrices 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén; Osuna Lucena, Amparo (Wiley, 2016)
      In this paper, we describe some necessary and sufficient conditions for a set of coboundaries to yield a cocyclic Hadamard ...
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      On ZZt × ZZ2 2-cocyclic Hadamard matrices 

      Álvarez Solano, Víctor; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén (Wiley, 2015)
      A characterization of ZZt × ZZ22 -cocyclic Hadamard matrices is described, de- pending on the notions of distributions, ...
    • Ponencia
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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)
      Progressing on a survey of the state of the art of cocyclic constructions for Hadamard matrices, we will prove that the ...
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      Pseudococyclic Partial Hadamard Matrices over Latin Rectangles 

      Falcón Ganfornina, Raúl Manuel; Álvarez, Víctor; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén (MDPI [Commercial Publisher], 2021-01-06)
      The classical design of cocyclic Hadamard matrices has recently been generalized by means of both the notions of the cocycle ...
    • Ponencia
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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)
      Three algorithms looking for pretty large partial Hadamard ma- trices are described. Here “large” means that hopefully ...