Inversion of sparse matrices with standard direct solve schemes is robust, but computationally expensive. Iterative solvers, on the other hand, demonstrate better scalability, but need to be used with an appropriate preconditioner (e.g., ILU, AMG, Gauss-Seidel, etc.) for proper convergence. The choice of an effective preconditioner is highly problem dependent. We propose a novel fully algebraic...

INTRODUCTION Anastomotic strictures occurring after colectomy are a most challenging postoperative complication for gastroenterological surgeons. Reports documenting anastomotic strictures developing in the early postoperative phase are scant, and no established treatment is available. PRESENTATION OF CASE A 78-year-old man who had undergone a laparoscopic left hemicolectomy for lower colon c...

In this report, using SEPRAN [1], the incompressible Stokes and Navier Stokes problems are solved in a square and L-shaped domain with a varying grid size and Reynolds number. Both problems are solved with iterative solvers using an ILU preconditioner. Different ordering techniques of the grid points and the unknowns are used to avoid breakdown of the LU decomposition. These ordering techniques...

Chemie Ingenieur TechnikVolume 94, Issue 9 p. 1299-1299 Vortrag Heterotrophic cultivation of Galdieria sulphuraria under non-sterile conditions in digestate and hydrolyzed straw D. Pleissner, Corresponding Author Pleissner [email protected] Institute for Food Environmental Research, Papendorfer Weg 3, 14806 Bad Belzig, GermanyCorrespondence: ([email protected]), GermanySearch ...

we used qcd factorization for the hadronic matrix elements to show that the existing data, in particular the branching ratios br ( ?j/?k) and br ( ?j/??), can be accounted for this approach. we analyzed the decay within the framework of qcd factorization. we have complete calculation of the relevant hard-scattering kernels for twist-2 and twist-3. we calculated this decays in a special scale ( ...

With the advent of detailed numerical models, computing runtime can become excessive. We propose the facilitation of an innovative multi-level inverse-based LU preconditioning approach to improve computational efficiency while processing EIT system matrices. This combines static reordering and scaling, controlled growth of the inverse of triangular factors and approximation of the Schurcompleme...

ILU(k) is an important preconditioner widely used in many linear algebra solvers for sparse matrices. Unfortunately, there is still no highly scalable parallel ILU(k) algorithm. This paper presents the first such scalable algorithm. For example, the new algorithm achieves 50 times speedup with 80 nodes for general sparse matrices of dimension 160,000 that are diagonally dominant. The algorithm ...

The streamed storage format for sparse matrices showed good performance improvement for sparse matrix and vector multiply (SpMV) compared with compressed sparse row (CSR) and block CSR (BCSR) formats, particularly on IBM Power processors. We extend the format to exploit single instruction multiple data (SIMD) instructions in order to utilize the vector unit, and discuss how the streamed formats...

Sparse linear systems are ubiquitous in various scientific computing applications. Inversion of sparse matrices with standard direct solve schemes are prohibitive for large systems due to their quadratic/cubic complexity. Iterative solvers, on the other hand, demonstrate better scalability. However, they suffer from poor convergence rates when used without a preconditioner. There are many preco...