Emission of ammonia and nitrogen oxides puts pressure on vulnerable ecosystems in The Netherlands. Satellite data from TROPOMI and CrIS gives vertical column density (VCD) maps for nitrogen dioxide and ammonia respectively. The Flux-Divergence method converts a VCD map to an emission map, by temporally averaging the divergence of the flux of the trace gas and estimating a sink term. This research proposes two improvements to the current implementation of the Flux-Divergence method at the KNMI for nitrogen dioxide. On the one hand, noise is reduced by computing the divergence before interpolating TROPOMI data to a regular grid. On the other hand, some emission locations are enhanced by reducing divergence in the wind field. An algorithm is provided to reduce this divergence. This thesis also explores the sensitivities of the method to different choices in its implementation. Finally, this research implements the Flux-Divergence method for ammonia. The thesis shows that, for ammonia, the method depends strongly on the estimation of the sink term, as the flux-divergence map is not able to capture homogeneous, spread-out emission sources.

The aim of this Bachelor Thesis is to extend the orthogonal projection method described in 'An Orthogonal Projection Method for Computing Active, Reactive and Scattered Power and its Application to Compensator Design' by Jacob van der Woude and Dimitri Jeltsema. In the aforementioned article, a method is described to calculate the active, reactive and scattered power of a RLC network. It uses an orthogonal projection of the current on the space of (anti)derivatives of the voltage. This method can be used to improve the power factor of the network, as it also shows how to design a compensator for the reactive power. The compensator consists of a parallel connection of an electromagnetic coil and a capacitor. Two working examples are given. This research shows that Van der Woude and Jeltsema's method is not always applicable. It often results in negative values for the coil and the capacitor, although this has no physical meaning. When the given voltage consists of more than two frequencies, the method is also inapplicable. This research gives a condition that ensures an applicable execution of this method. It also shows when these conditions are met. We show how the method can be extended to a working method for any RLC network, provided the voltage consists of two frequencies. It uses a second Foster canonical form to expand the initially proposed compensator. Depending on the coefficients given by the orthogonal projection, a different type of compensator is needed. It is also described how a fitting compensator can be chosen, and how the coefficients for the coils and capacitors can be determined.