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380
Dihedral Golay Sequences
, 1998
"... Dihedral Golay sequences are introduced and found for lengths 7,9,15, and 19. Applications include new classes of signed group Hadamard matrices and 19 real Hadamard matrices of orders 2tp, p S 4169. ..."
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Dihedral Golay sequences are introduced and found for lengths 7,9,15, and 19. Applications include new classes of signed group Hadamard matrices and 19 real Hadamard matrices of orders 2tp, p S 4169.
Grouptype subfactors and Hadamard matrices
"... A hyperfinite II1 subfactor may be obtained from a symmetric commuting square via iteration of the basic construction. For certain commuting squares constructed from Hadamard matrices, we describe this subfactor as a grouptype inclusion R H ⊂ R ⋊ K, where H and K are finite groups with outer action ..."
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Cited by 4 (0 self)
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A hyperfinite II1 subfactor may be obtained from a symmetric commuting square via iteration of the basic construction. For certain commuting squares constructed from Hadamard matrices, we describe this subfactor as a grouptype inclusion R H ⊂ R ⋊ K, where H and K are finite groups with outer
Hadamard and Conference Matrices
, 2001
"... We discuss new constructions of Hadamard and conference matrices using relative difference sets. We present the first example of a relative (n, 2, n − 1, n−2 2)difference set where n − 1 is not a prime power. ..."
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We discuss new constructions of Hadamard and conference matrices using relative difference sets. We present the first example of a relative (n, 2, n − 1, n−2 2)difference set where n − 1 is not a prime power.
The 2Transitive Complex Hadamard Matrices
, 2001
"... We determine all possibilities for a complex Hadamard matrix H admitting an automorphism group which permutes 2transitively the rows of H. Our proof of this result relies on the classification theorem for finite 2transitive permutation groups, and thereby also on the classification of finite simp ..."
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We determine all possibilities for a complex Hadamard matrix H admitting an automorphism group which permutes 2transitively the rows of H. Our proof of this result relies on the classification theorem for finite 2transitive permutation groups, and thereby also on the classification of finite
On the Asymptotic Existence of Cocyclic Hadamard Matrices
, 2009
"... Let q be an odd natural number. We prove there is a cocyclic Hadamard matrix of order 2 10+t q whenever t ≥ 8 ⌊ log 2 (q−1) 10 ⌋. We also show that if the binary expansion of q contains N ones, then there is a cocyclic Hadamard matrix of order 2 4N−2 q. 1 ..."
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Cited by 2 (0 self)
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Let q be an odd natural number. We prove there is a cocyclic Hadamard matrix of order 2 10+t q whenever t ≥ 8 ⌊ log 2 (q−1) 10 ⌋. We also show that if the binary expansion of q contains N ones, then there is a cocyclic Hadamard matrix of order 2 4N−2 q. 1
A system of equations for describing cocyclic Hadamard matrices
 J. COMB. DES
"... Given a basis B = {f1,..., fk} for 2cocycles f: G×G → {±1} over a group G of order G = 4t, we describe a nonlinear system of 4t − 1 equations and k indeterminates xi over ZZ2, 1 ≤ i ≤ k, whose solutions determine the whole set of cocyclic Hadamard matrices over G, in the sense that (x1,..., xk ..."
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Cited by 5 (2 self)
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Given a basis B = {f1,..., fk} for 2cocycles f: G×G → {±1} over a group G of order G = 4t, we describe a nonlinear system of 4t − 1 equations and k indeterminates xi over ZZ2, 1 ≤ i ≤ k, whose solutions determine the whole set of cocyclic Hadamard matrices over G, in the sense that (x1
EMBEDDING COCYCLIC DOPTIMAL DESIGNS IN COCYCLIC HADAMARD MATRICES ∗
"... Abstract. A method for embedding cocyclic submatrices with “large ” determinants of orders 2t in certain cocyclic Hadamard matrices of orders 4t is described (t an odd integer). If these determinants attain the largest possible value, we are embedding Doptimal designs. Applications to the pivot val ..."
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Abstract. A method for embedding cocyclic submatrices with “large ” determinants of orders 2t in certain cocyclic Hadamard matrices of orders 4t is described (t an odd integer). If these determinants attain the largest possible value, we are embedding Doptimal designs. Applications to the pivot
Direct Allocating the Dihedral Transformation for Fractal Image Compression
 Journal of Information Science and Engineering
, 2007
"... Fractal image compression exploits the selfsimilarity of an image to achieve the purpose of compression. In the standard algorithm, eight Dihedral transformations are applied on domain blocks to increase the codebook size, and therefore, the quality of reconstructed image can be improved. However, ..."
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Cited by 1 (1 self)
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Fractal image compression exploits the selfsimilarity of an image to achieve the purpose of compression. In the standard algorithm, eight Dihedral transformations are applied on domain blocks to increase the codebook size, and therefore, the quality of reconstructed image can be improved. However
Results 1  10
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380