Inward continuation of the scalp potential distribution by means of the (vector) BEM

The vector Boundary Element Method (vBEM) is used for the calculation of a matrix that links the tangential components of the current density on the cortical and scalp surface. This so-called transfer matrix is compared to the transfer matrix that links the potential distribution on both surfaces. Forward and inverse calculations are performed to evaluate both types of transfer matrice

Solving Vertical Transport and Chemistry in Air Pollution Models.

For the time integration of stiff transport-chemistry problems from air pollution modelling, standard ODE solvers are not feasible due to the large number of species and the 3D nature. The popular alternative, standard operator splitting, introduces artificial transients for short-lived species. This complicates the chemistry solution, easily causing large errors for such species. In the framework of an operational global air pollution model, we focus on the problem formed by chemistry and vertical transport, which is based on diffusion, cloud-related vertical winds, and wet deposition. Its specific nature leads to full Jacobian matrices, ruling out standard implicit integration. We compare Strang operator splitting with two alternatives: source splitting and an (unsplit) Rosenbrock method with approximate matrix factorization, all having equal computational cost. The comparison is performed with real data. All methods are applied with half-hour time steps, and give good accuracies. Rosenbrock is the most accurate, and source splitting is more accurate than Strang splitting. Splitting errors concentrate in short-lived species sensitive to solar radiation and species with strong emissions and depositions

The Leptophlebiidae : Atalophlebiinae of New Caledonia (Ephemeroptera) : part 5 : systematics

Cinquième d'une série sur des #Leptophlebiidae (#Ephemeroptera) de Nouvelle Calédonie, ce travail traite trois genres nouveaux, #Fasciamirus, Simulacala et #Kouma, et huit espèces nouvelles, #Fasciamirus rae, Simulaccala notialis, S. milleti, S. massula, Kouma adusta, K. annulata, K. becki et #K. aurata. Ces genres ont été décrits à partir des stades larvaires et adultes. (Résumé d'auteur

The influence of fetoabdominal volume conduction on the fetal MCG

In this paper five volume-conductor models are compared to estimate its influence on the fetal MCG and to determine whether a standardized model can be used to reconstruct the heart vector. For example, near term about two thirds of the fetuses is lying in a left occipital lateral position and one third in the right. Hence, two models, one describing the fetus in a left occipital lateral position and one mirrored in the sagittal plane, may be sufficient to reconstruct the heart vector

Asset management argunents for smart grids

This paper describes how Essent Netwerk has developed a strategy for the automation of its medium voltage network. Using Asset Management techniques, it was demonstrated that the application of a new distribution automation concept results in an improvement of network reliability and enables the temporisation of asset replacement programs. Both these benefits were quantified and appeared to outweigh the cost of the new strategy by fa