In many large scale scientiic and engineering computations, the solution to a sparse linear system is required. We present a partial unsymmetric nested dissection method that can be used to parallelize any general unsymmetric sparse matrix algorithm whose pivot search can be restricted to a subset of rows and columns in the active submatrix. The submatrix is determined by the partial unsymmetri...

A new unsymmetric matrix, SZu (unsymmetric Szeged matrix) is proposed by analogy to the matrix CJu (unsymmetric Cluj matrix) [1,2]. It is defined and exemplified both for acyclic and cycle-containing structures. Its relation with the CJu matrix is discussed. The derived Szeged numbers are compared to the Wiener matrixand Cluj matrixderived numbers and tested for separating and correlating abili...

efficient mode shape extraction of fluid-structure systems is of particular interest in engineering. an efficient modified version of unsymmetric lanczos method is proposed in this paper. the original unsymmetric lanczos method was applied to general form of unsymmetric matrices, while the proposed method is developed particularly for the fluid-structure matrices. the method provides us with si...

A new unsymmetric thioether diamine N - ( 2 - ( 2 - aminophenylthio) ethyl) benzene - 1 , 2 - diamine was prepared through the nucleophilic substitution of cysteaminium chloride with 1 - chloro - 2 - nitrobenzene and then the nitro groups of prepared compuond converted to the amine by zinc powder and ammonium chloride. Then, unsymmetric Schiff bass ligand 2 - ((( 2 - (( 2 - (( 2 - (( 2 - hydrox...

Efficient mode shape extraction of fluid-structure systems is of particular interest in engineering. An efficient modified version of unsymmetric Lanczos method is proposed in this paper. The original unsymmetric Lanczos method was applied to general form of unsymmetric matrices, while the proposed method is developed particularly for the fluid-structure matrices. The method provides us with si...

Supernode partitioning for unsymmetric matrices together with complete block diagonal supernode pivoting and asynchronous computation can achieve high gigaflop rates for parallel sparse LU factorization on shared memory parallel computers. The progress in weighted graph matching algorithms helps to extend these concepts further and unsymmetric prepermutation of rows is used to place large matri...

2 Sparse Matrices ……………………………………………………………………………… 4 2.1 The direct solution of sparse unsymmetric linear sets of equations (I.S. Duff and J.K. Reid) …………………………………………………………………………… 4 2.2 The design and use of algorithms for permuting large entries to the diagonal 2.6 Element resequencing for use with a multiple front solver (J. A. Scott) ………… 10 2.7 Exploiting zeros on the diagonal in the direct s...

We present algorithms for the symbolic and numerical factorization phases in the direct solution of sparse unsymmetric systems of linear equations. We have modified a classical symbolic factorization algorithm for unsymmetric matrices to inexpensively compute minimal elimination structures. We give an efficient algorithm to compute a near-minimal data-dependency graph for unsymmetric multifront...

In this paper we investigate a method to improve the performance of sparse LU matrix factorization used to solve unsymmetric linear systems, which appear in many mathematical models. We introduced and used the concept of the supernode for unsymmetric matrices in order to use dense matrix operations to perform the LU factorization for sparse matrices. We describe an algorithm that uses supernode...

Z. Naturforsch. 58b, 211 – 216 (2003); received Oktober 4, 2002 The oxidative coupling of various symmetric (5 7) as well as unsymmetric silicon bisnaphtholates (11, 12), initiated by different oxidants (iron(III), cerium(IV), copper(II) or hypervalent iodine), furnishes the corresponding symmetric and unsymmetric binaphthols 13 17. The coupling reaction of the substrates follows strictly an in...