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Het schermen is een vrij onbekende sport ondanks zijn olympische status. De sport bestaat al geruime tijd en desondanks is er in deze sport weinig wetenschappelijk onderzoek gedaan. Een discussie die zeer actueel is, is wat nu de beste uitvalstechniek in Heren Floret is. De uitval is de meest gebruikte aanvalsactie in het hedendaagse schermen. In dit bachelorproject zijn twee zogenaamde gegeneraliseerde lineaire modellen gebruikt om te onderzoeken welke uitvalstechniek de beste is.

Na het inleidende hoofdstuk 1 wordt in hoofdstuk 2 het probleem met betrekking tot de dijken langs de Afgedamde Maas en het Heusdensch Kanaal globaal aangegeven. Hoofdstuk 3 geeft een algemeen overzicht van de ontwikkelingen met betrekking tot de dijkverbeteringsproblematiek. Tevens worden de ontwikkelingen rond de dijkverbetering langs de Maas besproken en wordt een overzicht van de normen gegeven, die worden aangehouden bij de dijkverbetering. In hoofdstuk 4 worden de projectgrenzen aangegeven en wordt een historische schets van de wijzigingen in de Maasstroom gegeven. Daarnaast wordt de huidige toestand van het onderzoeksgebied en van de dijken langs de Afgedamde Maas en het Heusdensch Kanaal besproken. In hoofdstuk 5 wordt een globaal onderzoek naar het waterkerend vermogen van de huidige dijken langs de Afgedamde Maas en het Heusdensch Kanaal verricht. De huidige toestand van de dijken wordt gecontroleerd op de kruinhoogte, hydraulische grondbreuk, zandmeevoerende wellen, afschuiving binnentalud en afschuiving buitentalud. Op grond van het globale onderzoek wordt in hoofdstuk 6 het probleem met betrekking tot de dijken langs de Afgedamde Maas en het Heusdensch Kanaal aangegeven. Hoofdstuk 7 geeft, uitgaande van het probleem, de doelstelling aan. Tevens worden de uitgangspunten en de randvoorwaarden aangegeven die worden aangehouden bij het oplossen van het probleem. In hoofdstuk 8 komen de belangen in het onderzoeksgebied aan de orde die bij de keuze van een oplossing voor het probleem een rol zullen spelen. Hoofsdtuk 9 bespreekt de oplossingen voor de problematiek in het onderzoeksgebied. In hoofdstuk 10 worden twee alternatieven gekozen die nader worden uitgewerkt. Deze alternatieven kunnen als twee uitersten worden beschouwd. In hoofdstuk 11 wordt op grond van een aantal criteria een keuze gemaakt tussen de twee uitgewerkte alternatieven. Hoofdstuk 12 geeft tenslotte een overzicht van de conclusies en aanbevelingen die op grond van deze hoofdstudie zijn getrokken respectievelijk zijn opgesteld.

Discontinuous Galerkin (DG) methods are finite element techniques for the solution of partial differential equations. They allow shape functions which are discontinuous across inter-element edges. In principle, DG methods are ideally suited for hp-adaptivity, as they handle nonconforming meshes and varying-in-space polynomial-degree approximations with ease. Recently, DG formulations for elliptic problems have been put in a general framework of analysis. Although clarifying basic properties, the analysis does not warrant a clear preference. Specifically, none of the conventional DG formulations possesses a bilinear form that is coercive (and continuous) on an infinite-dimensional broken Sobolev space. Rather, bilinear forms are only weakly coercive or defined on subspaces only and employ stabilization parameters that typically increase unboundedly as the subspace is expanded, e.g., if the polynomial degree is increased. For hp-adaptation, coercivity is a fundamental property: By the classical Lax-Milgram theorem, any conforming discretization of a coercive formulation is stable, i.e., discrete approximations are well-posed and have a unique solution, irrespective of the specifics of the underlying approximation space. In this thesis we consider the one-dimensional Poisson problem and present a generic consistent conventional DG formulation. We show that conventional DG formulations are necessarily noncoercive. Moreover, we presents a new symmetric DG formulation which contains nonconventional edge terms based on element Green's functions and the data local to the edges. We show that the new DG formulation is coercive on H1(Ph), the space of functions that are piecewise in the H1 Sobolev space. Furthermore, we show that the new DG formulation and the classical Galerkin formulation are equivalent, that is, in the infinite-dimensional case they yield the same solution.

This Master Thesis presents a numerical model analysis of the response of the Rhine ROFI on wind direction and speed. The aim of this study is to gain a further insight in the physical processes of the Rhine ROFI. Previous work on the Rhine ROFI focused mostly on tidal effects (straining and mixing) and inertial motions (earth rotation). Other studies have focussed on the response of freshwater plumes to wind forcing alone. Recently, the combined forcing has been studied in an idealised model of the Rhine ROFI. The current study extends this research, however with the incorporation of the actual bathymetry and coastline of the Netherlands in a new, state-of-the-art three-dimensional hydrodynamic model. A sensitivity analysis of the number and distribution of vertical layers in the model found that 48 vertical layers is recommended under strongly stratified conditions The numerical results show that the effect of earths rotation on the wind-drive flow plays an important role in the stratification of the Rhine ROFI. Under neap tide conditions the Rhine ROFI exhibits periods of stratification. Due to a reduced eddy viscosity at the pycnocline in between, the surface layer responds more independently and is less affected by bottom friction. It implies that Coriolis force becomes relatively more important in the dynamics of the surface layer. Differential advection and depth mean advection make the size and shape of the freshwater plume highly variable. If the system is forced by an upwelling-favourable wind the freshwater plume is transported offshore, resulting in an increase of stratification. Downwelling-favourable winds transport the freshwater landwards, which results in a vertically well-mixed water column. An increased magnitude of the wind causes a more stratified water column for the upwelling-favourable winds and a more mixed state for the downwelling-favourable winds. Direct wind-induced vertical mixing of the plume is observed for an increased magnitude of the wind. The integrated potential energy anomaly is presented. It is found to be a powerful tool in analysing the interaction and competition of the wind and the ebb-flood tidal cycle in mixing and straining of the Rhine ROFI. The mixing and straining by the ebb-flood tidal cycle is found to be dominant over the mixing and straining by the wind. The influence of the wind on the Rhine ROFI is however clearly observed. The spatial changes in the potential energy anomaly show that for upwelling-favourable winds an increase of stratification occurs in the far-field. In the near-field a decrease is observed. For downwelling-favourable winds the opposite happens. The influence of the Ekman dynamics is observed in the results. For increased downwelling-favourable winds a reduction of the potential energy anomaly is found in both the near- and far-field of the Rhine ROFI.

The potential ecological effects of the sand mining activities for Maasvlakte 2 have been identified in an Environmental Impact Assessment (EIA). One of the identified effects in this EIA was an impact on the number of sea ducks in the Natura 2000 area 'Voordelta'. The sand mining activities will cause an increase of the silt concentration along the North Sea coast. Subsequently the light intensity in the water column decreases. A change of the light intensity can affect the growth of phytoplankton. An impact on the growth of phytoplankton can finally affect higher-order species in the food chain: phytoplankton is eaten by bivalves and bivalves form the main food of sea ducks like eiders. Within this so-called impact-effect chain from sand mining to sea ducks, a large number of uncertainties play a role. In the EIA safe assumptions were used for a lot of these uncertainties. The final predicted impact is a result of the accumulation of several safe assumptions. Therefore, the probability of occurrence of this predicted impact will be small. Information on this probability of occurrence will be useful in the discussion about the necessity of mitigating and compensating measures. The main objective of this thesis is to give insight in the probability of occurrence of the possible effects of sand mining on sea ducks in the Voordelta. The research started by analysing which uncertain factors and processes have a large influence on the final result. A Monte Carlo analysis was used to take the uncertainties of these factors into account in the modelling of the ecological effects. Probability density functions were estimated for the relevant variables and were finally combined in the Monte Carlo analysis. From the results of the Monte Carlo analysis probability distribution functions for the impact of sand mining on eiders are derived. These probability distribution functions show that the probability that the sand mining activities for Maasvlakte 2 have a significant effect on eiders in the Voordelta is very small and can be considered negligible. In this thesis is shown that giving insight in the probability of occurrence of significant ecological effects by using a probabilistic analysis is possible. The methodology that is used in this thesis is also expected to be applicable for the assessment of ecological effects of other human activities.