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Groeneboom, P. (author)
We analyze nonparametric estimators for the distribution function of the incubation time in the singly and doubly interval censoring model. The classical approach is to use parametric families like Weibull, log-normal or gamma distributions in the estimation procedure. We propose nonparametric estimates for functions of the observations,...
journal article 2024
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Wijnands, R. (author), Dauwels, J.H.G. (author), Serra, Ines (author), Kruizinga, P. (author), Badura, Aleksandra (author), Hunyadi, Borbala (author)
Functional ultrasound (fUS) is a novel neuroimaging technique that measures brain hemodynamics through a time series of Doppler images. The measured spatiotemporal hemodynamic changes reflect changes in neural activity through the neurovascular coupling (NVC). Often, such image time series is used to analyze dynamic functional connectivity ...
conference paper 2023
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Su, Ruisheng (author), van der Sluijs, P. Matthijs (author), Bobi, Joaquim (author), Taha, Aladdin (author), van Beusekom, Heleen M.M. (author), van der Lugt, Aad (author), Niessen, W.J. (author), Ruijters, Danny (author), van Walsum, T. (author)
Background: X-ray digital subtraction angiography (DSA) is the imaging modality for peri-procedural guidance and treatment evaluation in (neuro-) vascular interventions. Perfusion image construction from DSA, as a means of quantitatively depicting cerebral hemodynamics, has been shown feasible. However, the quantitative property of perfusion...
journal article 2023
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Abdi, Bahareh (author)
Atrial fibrillation (AF) is a common age-related cardiac arrhythmia. AF is characterized by rapid and irregular electrical activity of the heart leading to a higher risk of stroke and heart failure. During AF, the upper chambers of the heart, called atria, experience chaotic electrical wave propagation. However, despite the various mechanisms...
doctoral thesis 2021
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Wilding, D. (author)
The goal of this thesis, called Physical and Computational Approaches to Aberration Correction In Fluorescence Microscopy, concerns itself with the development of new techniques to control adaptive fluorescence microscopes, so that they can adapt and image with increased resolution, contrast and speed inside complex three-dimensional biological...
doctoral thesis 2018
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Wilding, D. (author), Pozzi, P. (author), Soloviev, O.A. (author), Vdovin, Gleb (author), Fiolka, Reto (author), Verhaegen, M.H.G. (author)
The light-sheet fluorescence microscopy is an excellent tool for the investigation of large three dimensional microscopy samples at the cellular level, however, the ability to resolve features is strongly affected by the presence of scattering and aberrations. These effects are two fold in light-sheet microscopy, as the illumination path...
conference paper 2018
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Feld, R. (author)
Ground-penetrating radar (GPR) is a non-destructive method that images the subsurface using radar. A transmitter generates a radar pulse. This signal propagates into the ground where it reflects against subsurface heterogeneities, and travels back to the surface. A receiver records the reflected signal. The reflected signal contains information...
doctoral thesis 2017
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Sijtsma, P. (author), Merino Martinez, R. (author), Malgoezar, A.M.N. (author), Snellen, M. (author)
In this article, a high-resolution extension of CLEAN-SC is proposed: high-resolution-CLEAN-SC. Where CLEAN-SC uses peak sources in ‘dirty maps’ to define so-called source components, high-resolution-CLEAN-SC takes advantage of the fact that source components can likewise be derived from points at some distance from the peak, as long as these...
journal article 2017
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Weemstra, C. (author), Wapenaar, C.P.A. (author), Van Dalen, K.N. (author)
In this work we investigate a modification of the formulation of the theory underlying seismic interferometry (SI) by multidimensional deconvolution (MDD). The current formulation, and hence method, relies on separation of waves traveling inward and outward of a volume bounded by receivers. As a consequence, it is predominantly useful when...
conference paper 2015
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Righolt, C.H. (author), Mai, S. (author), Van Vliet, L.J. (author), Stallinga, S. (author)
The quality of the reconstructed image in structured illumination microscopy (SIM) depends on various aspects of the image filtering process. To optimize the trade-off between resolution and ringing artifacts, which lead to negative intensities, we extend Lukosz-bound filtering to 3D SIM and derive the parametrization of the 3D SIM cut-off. We...
journal article 2014
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Hunziker, J.W. (author), Slob, E.C. (author), Fan, Y. (author), Snieder, R. (author), Wapenaar, C.P.A. (author)
With interferometry applied to controlled-source electromagnetic data, the direct field and the airwave and all other effects related to the air-water interface can be suppressed in a data-driven way. Interferometry allows for retreival of the scattered field Green’s function of the subsurface or, in other words, the subsurface reflection...
journal article 2013
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Minato, S. (author), Matsuoka, T. (author), Tsuji, T. (author)
We have developed a method to analytically evaluate the relationship between the source-receiver configuration and the retrieved wavefield in seismic interferometry performed by multidimensional deconvolution (MDD). The MDD method retrieves the wavefield with the desired source-receiver configuration from the observed wavefield without source...
journal article 2013
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Korkiakoski, V. (author), Keller, C.U. (author), Doelman, N. (author), Fraanje, P.R. (author), Verhaegen, M.H.G. (author)
We study different possibilities to use adaptive optics (AO) and phase diversity (PD) together in a jointly optimized system. The potential of the joint system is demonstrated through numerical simulations. We find that the most significant benefits are obtained from the improved deconvolution of AO-corrected wavefronts and the additional...
journal article 2011
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Van der Neut, J.R. (author), Thorbecke, J.W. (author), Mehta, K. (author), Slob, E.C. (author), Wapenaar, C.P.A. (author)
Various researchers have shown that accurate redatuming of controlled seismic sources to downhole receiver locations can be achieved without requiring a velocity model. By placing receivers in a horizontal or deviated well and turning them into virtual sources, accurate images can be obtained even below a complex near-subsurface. Examples...
journal article 2011
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Hunziker, J.W. (author), Slob, E.C. (author), Wapenaar, C.P.A. (author)
In time-lapse controlled-source electromagnetics, it is crucial that the source and the receivers are positioned at exactly the same location at all times of measurement. We use interferometry by multidimensional deconvolution (MDD) to overcome problems in repeatability of the source location. Interferometry by MDD redatums the source to a...
journal article 2011
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Wapenaar, C.P.A. (author), Slob, E.C. (author), Snieder, R. (author), Curtis, A. (author)
In the 1990s, the method of time-reversed acoustics was developed. This method exploits the fact that the acoustic wave equation for a lossless medium is invariant for time reversal. When ultrasonic responses recorded by piezoelectric transducers are reversed in time and fed simultaneously as source signals to the transducers, they focus at the...
journal article 2010
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Jongbloed, G. (author), Van der Meulen, F.H. (author)
We consider two nonparametric procedures for estimating a concave distribution function based on data corrupted with additive noise generated by a bounded decreasing density on (0, ?). For the maximum likelihood (ML) estimator and least squares (LS) estimator, we state qualitative properties, prove consistency and propose a computational...
journal article 2009
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Van der Neut, J. (author), Bakulin, A. (author)
In the virtual source (VS) method we crosscorrelate seismic recordings at two receivers to create a new data set as if one of these receivers were a virtual source and the other a receiver. We focus on the amplitudes and kinematics of VS data, generated by an array of active sources at the surface and recorded by an array of receivers in a...
journal article 2009
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Slob, E.C. (author)
Interferometric techniques are now well known to retrieve data between two receivers by the cross correlation of the data recorded by these receivers. Cross-correlation methods for interferometry rely mostly on the assumption that the medium is loss free and that the sources are all around the receivers. A recently developed method introduced...
journal article 2009
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Vermolen, B.J. (author)
Cancer is one of the most well-known groups of diseases that finds its cause in cells having chromosomal aberrations. How and why these aberrations can occur is one of the most important questions asked in modern molecular biology. In the last decades it has become clear that gene regulation in the nucleus, where the chromosomes reside, is...
doctoral thesis 2009
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