In this paper, some properties of centrosymmetric matrices, which often appear in the construction of orthonormal wavelet basis in wavelet analysis, are investigated. As an application, an algorithm which is tightly related to a so-called Lawton matrix is presented. In this algorithm, about only half of memory units are required and quarter of computational cost is needed by exploiting the prop...

2 & 1 Depts. (P.G.&U.G.) Of Mathematics, Hindu College,Guntur – 522 002, Andhra Pradesh, INDIA. Ph: 0863 – 350818 (Res) E-Mail: [email protected] “ABSTRACT” We present recursive algorithms for finding the inverse of any nonsingular square matrix and in particular a positive definite symmetric (PDS) matrix through single bordering and double bordering and obtain the operational counts fo...

By Hermitian mapping, we suggest unitary cyclic root-MUSIC algorithm to exploit the signal selective property of cyclostationary signals in this paper. To deal with correlated or coherent case, we design the forward backward cyclic autocorrelation matrix, without conjugate centrosymmetric array configurations. Compared with unitary root-MUSIC algorithm, the proposed method has a better performa...

We characterize the sets of centrosymmetric permutations, namely, permutations σ ∈ Sn such that σ(i)+σ(n+1−i) = n+1, that avoid any given family of patterns of length 3. We exhibit bijections between some sets of restricted centrosymmetric permutations and sets of classical combinatorial objects, such as Dyck prefixes and subsets of [n] containing no consecutive integers.

A new non-centrosymmetric compound, tris-odium tetra-niobium triarsenic nona-deca-oxide, Na(3)Nb(4)As(3)O(19), has been synthesized by a solid-state reaction at 1123 K. The structure consists of AsO(4) tetra-hedra and NbO(6) octa-hedra sharing corners to form a three-dimensional framework containing two types of tunnels running along the c axis, in which the sodium ions are located. Na(+) catio...

Four more examples are provided to emphasize the extreme difficulty in deciding, by diffraction methods, whether a crystal structure is centrosymmetric or only approximately so. In these examples, earlier workers described and refined structures in noncentrosymmetric space groups; refinements in the corresponding centrosymmetric space groups, based on the original data, lead to improved results...