Generalized averaged Gaussian quadrature and applications

A simple numerical method for constructing the optimal generalized averaged Gaussian quadrature formulas will be presented. These formulas exist in many cases in which real positive GaussKronrod formulas do not exist, and can be used as an adequate alternative in order to estimate the error of a Gaussian rule. We also investigate the conditions under which the optimal averaged Gaussian quadrature formulas and their truncated variants are internal

MS FT-2-2 7 Orthogonal polynomials and quadrature: Theory, computation, and applications

Quadrature rules find many applications in science and engineering. Their analysis is a classical area of applied mathematics and continues to attract considerable attention. This seminar brings together speakers with expertise in a large variety of quadrature rules. It is the aim of the seminar to provide an overview of recent developments in the analysis of quadrature rules. The computation of error estimates and novel applications also are described

Efficient parallel implementation of the fully algebraic multiplicative Aitken-RAS preconditioning technique

International audienceThis paper details the software implementation of the ARAS preconditioning technique (Dufaud T, Tromeur- Dervout D. Aitken's acceleration of the Resctricted Additive Schwarz preconditioning using coarse approximations on the interface. CR Math Acad Sci Paris 2010;348(13-14):821-4), in the PETSc framework. Especially, the PETSc implementation of interface operators involved in ARAS and the introduction of a two level of parallelism in PETSc for the RAS are described. The numerical and parallel implementation performances are studied on academic and industrial problems, and compared with the RAS preconditioning. For saving computational time on industrial problems, the Aitken's acceleration operator is approximated from the singular values decomposition technique of the RAS iterate solutions

Advanced Computer Technologies for Integrated Agro-Hydrologic Systems Modeling: Coupled Crop and Hydrologic Models for Agricultural Intensification Impacts Assessment

Coupling hydrologic and crop models is increasingly becoming an important task when addressing agro-hydrologic systems studies. Either for resources conservation or cropping systems improvement, the complex interactions between hydrologic regime and crop management components requires an integrative approach in order to be fully understood. Nevertheless, the literature offers limited resources on models’ coupling that targets environmental scientists. Indeed, major of guides are are destined primarily for computer specialists and make them hard to encompass and apply. To address this gap, we present an extensive research to crop and hydrologic models coupling that targets earth agro-hydrologic modeling studies in its integrative complexity. The primary focus is to understand the relationship between agricultural intensification and its impacts on hydrologic balance. We provided documentations, classifications, applications and references of the available technologies and trends of development. We applied the results of the investigation by coupling the DREAM hydrologic model with DSSAT crop model. Both models were upgraded either on their code source (DREAM) or operational base (DSSAT) for interoperability and parallelization. The resulting model operates at a grid base and daily step. The model is applied southern Italy to analyze the effect of fertilizer application on runoff generation between 2000 and 2013. The results of the study show a significant impacts of nitrogen application on water yield. Indeed, nearly 71.5 thousand cubic-meter of rain water for every kilogram of nitrogen and per hectare is lost as a reduction of runoff coefficient. Furthermore, a significant correlation between the nitrogen applications amount and runoff is found at a yearly basis with Pearson’s coefficient of 0.93