Magnetic interpolation using Gaussian processes

In this thesis a model for interpolation of magnetic fields is constructed using Gaussian processes. This model takes the curl- and divergence-free properties of magnetic fields into account. The Gaussian process regression, or kriging, is tested on both simulated and real data. It is also attempted to reconstruct the magnetization of objects...

Designing a search-algorithm that uses an autonomously moving swarm of drones to eciently detect drifting steel shipping containers, using Magnetic Anomaly Detection and Simulated Annealing

This thesis explores different methodes to optimally guide a swarm of drones towards a steel shipping container. It does this using techniques such as Simulated Annealing and Magnetic Anomaly Detection. The drones will use Simulated Annealing in combination with Magnetic Anomaly Detection to estimate where the steel shipping container is located...

Total least squares method for the purpose of noise reduction in low-cost MRI images

MRI images are very useful for detecting diseases, as well as for the treatment of diseases. However, MRI scanners are usually too expensive for developing countries to purchase and maintain. Therefore, a less expensive scanner is being developed at Delft University of Technology and Leiden University Medical Center. Unfortunately, the images...

A study of Jacobian-free Newton Krylov methods and Schur complement parameters for solving coupled systems

Numerical models are paramount in describing the complex physical world around us. They are often based on non-linear functions, which have to be solved in order to run a simulation. The first goal of this thesis is to compare the Jacobian-free Newton-Krylov method against the regular Newton-Raphson method for solving non-linear equations. When...

Analysis of the impact of news on the financial market

In this work we set out to determine the impact, if any, of the analysis of news on stock price prediction, that is, are we able to predict stock movements more accurately on a consistent basis than a proposed baseline or random guessing on the basis of news’ text analysis. We considered a methodology to be more accurate if its success rate is...

Fatigue Modelling With A Two-Dimensional Spring Network

A random periodic two-dimensional spring network us built using a Poisson disk distribution and computing the Delaunay triangulation of the centers of the disks. The edges of the network represent springs that obey Hooke’s law with an adjustment on the spring constant. The adjustment allows spring to soften and to break. The two-dimensional...

Machine Learning Based Error Modeling for Surrogate Model in Oil Reservoir Problem

This thesis focuses on the construction and optimization of a prediction model for the errors resulting from a model order reduction (MOR) procedure in oil reservoir simulation. MOR is a numerical technique that projects the physical based model, which is also called the high-fidelity model (HFM), into a lower dimension by using matrix...

Optimization of in-depth divergence strategies

This study discusses the potential of the in-depth water diversion (IDD) process to enhance oil recovery from subsurface reservoirs and investigates IDD strategies through an ensemble optimization approach. Pilot studies in the North Sea performed in recent years have shown that Sodium Silicate can be applied as blocking agent, diverting water...

Redesign of the Solution Algorithms in Wanda

The Wanda software package developed by Deltares can used for simulating both steady state and transient fluid flow in pipeline systems. Steady state simulations are used for initial system design and transient flow simulations are used for doing water hammer analysis in pipeline systems. For both types of simulations a system consisting of both...

Convolution in Multiphase Flow Simulations: Improving Interface Curvature Estimations

The accurate approximation of the surface tension force is paramount for continuum surface models in the field of computational fluid dynamics for multiphase flow where surface tension is relevant. This involves being able to accurately calculate the curvature at the interface. This study focuses on the use of convolution in smoothing the VOF...

Wavelet analysis in the field of coastal engineering: Applications in time-series analysis

Time-frequency analysis and digital signal processing are important tools in the field of coastal engineering. Both can be done using techniques like Fourier or wavelet analysis, however, analysts from this field experience a threshold to use wavelet analysis instead of their current methods, often Fourier-based. This is due to the lack of...

Het effect van een anisotropiecoëfficiënt in de Poissonvergelijking op de convergentie van de CG-methode en de ICCG(0)-methode

Allerlei diffusieverschijnselen in de natuurkunde kunnen omschreven worden<br/>met de Poissonvergelijking op een gebied met te kiezen randvoorwaarden. Er zijn echter ook verschijnselen waarin er een gelaagdheid optreedt zodat er in verticale<br/>richting minder makkelijk diffusie kan plaatsvinden. Dit leidt tot een vergelijking<br/>met...