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Bouchan, Thomas (author)
Breast cancer is the most occurring cancer among women. Detecting it at an early stage enables to significantly reduce the mortality rate. Mammography is the golden standard technique used for screening but it has some disadvantages, among which the difficulty to scan women with dense breasts. Ultrasound is a promising technique enabling a cheap...
master thesis 2019
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SHARMA, Sparsh (author)
The increasing complexity of mechanical systems has resulted in an increased usage and dependence on data driven modelling techniques in order to obtain simple yet accurate models of these systems. Neural networks have emerged as a popular modelling choice due to their proven ability to learn complex nonlinear relationships between inputs and...
master thesis 2019
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Liu, Zheheng (author)
In this thesis, we investigate a sparse basis for ultrasound images, so that we can use sparse regularization in imaging. Actually, there are few previous researches explicitly demonstrating that medical ultrasound images can be sparsified for some dictionary. We consider various orthogonal transforms such as wavelet transforms, cosine...
master thesis 2019
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Visser, Adriaan (author)
This work determines whether the amount of frequency components present in the data can be reduced, whilst still retaining image quality, whereas most efforts in seismological research are done in reducing spatial sampling. It is shown using a PCA on the frequency spectra of several data sets that indeed a large redundancy in frequency content...
master thesis 2018
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Sigurbergsson, Bjorn (author)
The trend of computing faster and more efficiently has been a driver for the computing industry since its beginning. However, it is increasingly difficult to continue this trend because current CMOS technology cannot be down-scaled anymore due to physical restrictions. Consequently, to obtain the next major performance improvement, the focus is...
master thesis 2018
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Ortiz Jimenez, Guillermo (author)
In this era of data deluge, we are overwhelmed with massive volumes of extremely complex datasets. Data generated today is complex because it lacks a clear geometric structure, comes in great volumes, and it often contains information from multiple domains. In this thesis, we address these issues and propose two theoretical frameworks to handle...
master thesis 2018
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TZOTZADINIS, Chris (author)
Compressive Sensing (CS) provides a new paradigm in data acquisition and signal processing based on the assumption of sparsity and the incoherence of the received signal. Based on that concept, many radar front-end architectures have been studied with the implementation of CS. In these architectures, less data are collected but the radar scene...
master thesis 2017
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Varnai, Peter (author)
We study the important mathematical problem of approximating the inverse of low Kronecker-rank matrices in this same form. A traditional alternating least squares (ALS) scheme for solving such problems is presented, and we discuss two efficient solutions to the subproblems arising in the corresponding iterations. The first relies on a least...
master thesis 2017
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Ram, Raju (author)
Groundwater, present beneath the earth’s surface in soil pore spaces, is the primary source of fresh water that we use in day to day life. Hydrologists at Dutch research institute Deltares are developing large groundwater models to support water man- agers in their decision-making process. For example, these models simulate effects such as water...
master thesis 2017
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Taal, A.J. (author)
This thesis presents a novel nanophotonic Metal-Insulator-Metal (MIM) grating structure that diffracts incident light by filtering colour based on interference. The grating creates two independent self-images (Talbot patterns) for two almost arbitrarily tuneable wavelengths in the visible spectrum. Lens-less imaging is promising for its ability...
master thesis 2017
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Dominicus, S. (author)
The next generation of ground-based telescopes have a segmented primary mirror consisting of up to 800 segments which are mounted on a support truss. These segments are actively controlled to correct for external disturbances of which wind loading is the primary source. As mirror size and number of segments grows ever larger, dynamic coupling...
master thesis 2016
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Keijsers, J.G.M. (author)
Increasing demands for mobile internet access have led to exponential developments in mobile communications technologies. The next generation mobile technology is expected to exploit electronic beam steering and to have a higher operating frequency to facilitate a higher bandwidth. This places a heavy burden on the base station antenna arrays,...
master thesis 2016
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Zhang, R. (author)
In the recent development of wireless communication several applications, such as spectrum sensing for cognitive radio are only interested in the power spectrum. These applications do not require the reconstruction of the original analog signal. According to the Whittaker-Kotelnikov-Shannon-Nyquist theorem, the sampling rate must be at least...
master thesis 2015
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Desmedt, S.G.L. (author)
The area of interest for this study is the field of uncertainty quantification in computational fluid dynamics. The goal is to contribute to a new method to perform uncertainty quantification analyses for industrial, computationally expensive CFD simulations. To this end, an adaptive grid refinement method is developed. The existing sparse grid...
master thesis 2015
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Hu, K. (author)
Near-field source localization is an important aspect in many diverse areas such as acoustics, seismology, to list a few. The planar wave assumption frequently used in far-field source localization is no longer valid when the sources are in the near field. Near-field sources can be localized by solving a joint direction-of-arrival and range...
master thesis 2014
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Shakeri, S. (author)
In this work a new location fingerprinting-based localization algorithm is proposed for an underwater medium by utilizing ultra-wideband (UWB) signals. In many conventional underwater systems, localization is accomplished by utilizing acoustic waves. On the other hand, electromagnetic waves haven't been employed for underwater localization due...
master thesis 2012
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De Jong, M.A. (author)
The Maritime Research Institute Netherlands (MARIN) supplies innovative products for the offshore industry and shipping companies. Among their products are highly realistic real-time bridge simulators. Currently, the waves are deterministic and are not affected by ships, moles, breakwaters, piers, or any other object. To bring the simulators to...
master thesis 2012
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Kästner, K. (author)
This thesis is about the numerical approximation of the spectrum of the confined hydrogen atom. The energy levels and wave functions of the hydrogen atom are modelled by the corresponding eigenvalues and eigenvectors of the Schrödinger equation with Coulomb potential. At first different discretisation techniques for the hydrogenic Schrödinger...
master thesis 2012
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Wildeboer, M.E. (author)
Matrices zijn objecten die vrij centraal staan in de studie der wiskunde. Ze worden gebruikt om data te representeren, zoals grafen en stelsels van lineaire vergelijkingen. Soms kan het handig zijn om zo'n willekeurige matrix te kunnen benaderen met een 'schaarse' of 'gestructureerde' matrix. Nadruk ligt hierbij op het feit dat de benadering...
bachelor thesis 2012
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Jacobs, A.G.M.M. (author)
bachelor thesis 2011
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