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Mostrando ítems 1-10 de 46
Ponencia
On the computability of the p-local homology of twisted cartesian products of Eilenberg-Mac Lane spaces
(Universidade do Minho, 1997)
Working in the framework of the Simplicial Topology, a method for calculating the p-local homology of a twisted cartesian product X( , m, , 0, n) = K( ,m)× K( 0, n) of Eilenberg-Mac Lane spaces is given. The chief ...
Artículo
A computational algebraic geometry approach to analyze pseudo-random sequences based on Latin squares
(Springer, 2019)
Latin squares are used as scramblers on symmetric-key algorithms that generate pseudo-random sequences of the same length. The robustness and effectiveness of these algorithms are respectively based on the extremely large ...
Ponencia
Error correcting codes from quasi-Hadamard matrices
(Springer, 2007)
Levenshtein described in [5] a method for constructing error correcting codes which meet the Plotkin bounds, provided suitable Ha- damard matrices exist. Uncertainty about the existence of Hadamard matrices on all orders ...
Artículo
Algebra Structures on the Comparison of the Reduced Bar Construction and the Reduced W-Construction
(Taylor and Francis, 2009)
For a simplicial augmented algebra K, Eilenberg–Mac Lane constructed a chain map . They proved that g is a reduction (homology isomorphism) and conjectured that it is also the injection of a contraction (special homotopy ...
Ponencia
Homological perturbation theory and computability of Hochschild and cyclic homologies of CDGAs
(Diffiety Institute of the Russian Academy of Natural Sciences, 1997)
We establish an algorithm computing the homology of commutative differential graded algebras (briefly, CDGAs). The main tool in this approach is given by the Homological Perturbation Theory particularized for the algebra ...
Artículo
On Cocyclic Hadamard Matrices over Goethals-Seidel Loops
(MDPI, 2020)
About twenty-five years ago, Horadam and de Launey introduced the cocyclic development of designs, from which the notion of cocyclic Hadamard matrices developed over a group was readily derived. Much more recently, it ...
Artículo
A Mixed Heuristic for Generating Cocyclic Hadamard Matrices
(Springer, 2018)
A way of generating cocyclic Hadamard matrices is described, which combines a new heuristic, coming from a novel notion of fitness, and a peculiar local search, defined as a constraint satisfaction problem. Calculations ...
Artículo
On ZZt × ZZ2 2-cocyclic Hadamard matrices
(Wiley, 2015)
A characterization of ZZt × ZZ22 -cocyclic Hadamard matrices is described, de- pending on the notions of distributions, ingredients and recipes. In particular, these notions lead to the establishment of some bounds on ...
Artículo
On D4t-Cocyclic Hadamard Matrices
(Wiley, 2016)
In this paper, we describe some necessary and sufficient conditions for a set of coboundaries to yield a cocyclic Hadamard matrix over the dihedral group D4t. Using this characterization, new classification results for ...
Artículo
Determinants of (–1,1)-matrices of the skew-symmetric type: a cocyclic approach
(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 = −kj,i. The largest possible determinant of such a matrix K is an interesting problem. The literature ...