The finite element Laplace transform integration of nonequilibrium or nonideal contaminant transport in porous media yields complex unsymmetric equations which are to be repeatedly solved for several (typically ) complex-valued Laplace parameters in the Laplace domain. The solutions may be obtained with the aid of iterative projection methods such as Bi-CGSTAB (BiConjugate Gradient STABilized) ...

Based on the premise that preconditioners needed for scientific computing are not only required to be robust in the numerical sense, but also scalable for up to thousands of light-weight cores, we argue that this two-fold goal is achieved for the recently developed self-adaptive multi-elimination preconditioner. For this purpose, we revise the underlying idea and analyze the performance of impl...

This paper analyzes the performance of a few preconditioners for solving the complex linear systems which originate from the application of real space pseudopotential methods in the study of electron transport properties of nanoscale junctions. These linear systems of equations are part of a self-consistent loop to compute the charge density and corresponding potential at the nanoscale junction...

we prove that the class of profinite groups $g$ that have a factorization $g=ab$ with $a$ and $b$ abelian closed subgroups, is closed under taking strict projective limits. this is a generalization of a recent result by k.h.~hofmann and f.g.~russo. as an application we reprove their generalization of iwasawa's structure theorem for quasihamiltonian pro-$p$ groups.

We are interested in bridging the world of natural language and the world of the semantic web in particular to support natural multilingual access to the web of data. In this paper we introduce a new type of lexical ontology called interlingual lexical ontology (ILexicOn), which uses semantic web formalisms to make each interlingual lexical unit class (ILU) support the projection of its semanti...

In this paper, efficient direct and iterative methods are described for solving a large random sparse non-symmetric linear system. Such systems of linear equations of huge order arise in several applications such as physics, mechanics, signal processing and other applications of real life problems. For this reason, we try to develop direct and iterative methods for solving such systems of linea...

We investigate the use of sparse approximate inverse techniques in a multilevel block ILU preconditioner to design a robust and efficient parallelizable preconditioner for solving general sparse matrices. The resulting preconditioner retains robustness of the multilevel block ILU preconditioner (BILUM) and offers a convenient means to control the fill-in elements when large size blocks (subdoma...