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Verweij, Peter (author)
In this report, the design process of a high precision positioning system for Ghana is described. The system consists of two devices, a base station and a user operated rover. These devices provide precision positioning, using dual frequency receivers and the principle of differential positioning. The high precision positioning system can be...
master thesis 2020
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Beekers, D.I. (author), Vegter, Merel (author), Lattwein, Kirby R. (author), Mastik, Frits (author), Beurskens, Robert (author), van der Steen, A.F.W. (author), de Jong, N. (author), Verweij, M.D. (author), Kooiman, Klazina (author)
Ultrasound insonification of microbubbles can locally increase vascular permeability to enhance drug delivery. To control and optimize the therapeutic potential, we need to better understand the underlying biological mechanisms of the drug delivery pathways. The aim of this in vitro study was to elucidate the microbubble-endothelial cell...
journal article 2020
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Massaad Mouawad, J.M. (author), van Neer, P.L.M.J. (author), Willigen, D. M. van (author), Pertijs, M.A.P. (author), de Jong, N. (author), Verweij, M.D. (author)
During ultrasonic clamp-on flow metering, Lamb waves propagating in the pipe wall may limit the measurement accuracy by introducing absolute errors in the flow estimates. Upon reception, these waves can interfere with the up and downstream waves refracting from the liquid, and disturb the measurement of the transit time difference that is used...
journal article 2020
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Mozaffarzadeh, M. (author), Minonzio, C.G. (author), de Jong, N. (author), Verweij, M.D. (author), Hemm, Simone (author), Daeichin, V. (author)
Phase aberration in transcranial ultrasound imaging (TUI) caused by the human skull leads to an inaccurate image reconstruction. In this article, we present a novel method for estimating the speed of sound and an adaptive beamforming technique for phase aberration correction in a flat polyvinylchloride (PVC) slab as a model for the human...
journal article 2020
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Massaad Mouawad, J.M. (author), van Neer, P.L.M.J. (author), van Willigen, D.M. (author), Pertijs, M.A.P. (author), de Jong, N. (author), Verweij, M.D. (author)
Current ultrasonic clamp-on flow meters are manually calibrated. This process is based on manual placement of two single-element transducers along a pipe wall. Due to the usually unknown pipe properties and inhomogeneities in the pipe geometry, the axial distance of the transducers needs to be manually calibrated to align the location of the...
journal article 2020
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Kooiman, Klazina (author), Roovers, Silke (author), Langeveld, Simone A.G. (author), Kleven, Robert T. (author), Dewitte, Heleen (author), O'Reilly, Meaghan A. (author), Escoffre, Jean Michel (author), Bouakaz, Ayache (author), Verweij, M.D. (author)
Therapeutic ultrasound strategies that harness the mechanical activity of cavitation nuclei for beneficial tissue bio-effects are actively under development. The mechanical oscillations of circulating microbubbles, the most widely investigated cavitation nuclei, which may also encapsulate or shield a therapeutic agent in the bloodstream,...
review 2020
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Sabbadini, A. (author), Keijzer, L.B.H. (author), Vos, H.J. (author), de Jong, N. (author), Verweij, M.D. (author)
Shear wave elastography (SWE) might allow non-invasive assessment of cardiac stiffness by relating shear wave propagation speed to material properties. However, after aortic valve closure, when natural shear waves occur in the septal wall, the stiffness of the muscle decreases significantly, and the effects of such temporal variation of...
journal article 2020
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Beekers, D.I. (author), Mastik, Frits (author), Beurskens, Robert (author), Tang, Phoei Ying (author), Vegter, Merel (author), van der Steen, A.F.W. (author), de Jong, N. (author), Verweij, M.D. (author), Kooiman, Klazina (author)
Ultrasound insonification of microbubbles can locally enhance drug delivery, but the microbubble–cell interaction remains poorly understood. Because intracellular calcium (Ca<sub>i</sub> <sup>2+</sup>) is a key cellular regulator, unraveling the Ca<sub>i</sub> <sup>2+</sup> fluctuations caused by an oscillating microbubble provides crucial...
journal article 2020
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Mozaffarzadeh, M. (author), Minonzio, C.G. (author), de Jong, N. (author), Verweij, M.D. (author), Hemm, Simone (author), Renaud, G.G.J. (author), Daeichin, V. (author)
In the above article [1], we mentioned that the superposition of the different symmetric (S) modes in the frequencywavenumber (f-k) domain results in a high-intensity region where its slope corresponds to the longitudinal wave speed in the slab. However, we have recently understood that this highintensity region belongs to the propagation of...
journal article 2020
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Chen, Z. (author), Soozande, M. (author), Vos, H.J. (author), Bosch, J.G. (author), Verweij, M.D. (author), de Jong, N. (author), Pertijs, M.A.P. (author)
This article quantitatively analyzes the impact of bit errors in digitized RF data on ultrasound image quality. The quality of B-mode images in both linear array and phased array imaging is evaluated by means of three objective image quality metrics: peak signal-to-noise ratio, structural similarity index, and contrast-to-noise ratio, when...
journal article 2020
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Mozaffarzadeh, M. (author), Soozande, M. (author), Fool, F. (author), Pertijs, M.A.P. (author), Vos, H.J. (author), Verweij, M.D. (author), Bosch, Johan G. (author), de Jong, N. (author)
Recently, we realized a prototype matrix transducer consisting of 48 rows of 80 elements on top of a tiled set of Application Specific Integrated Circuits (ASICs) implementing a row-level control connecting one transmit/receive channel to an arbitrary subset of elements per row. A fully sampled array data acquisition is implemented by a...
journal article 2020
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van Willigen, D.M. (author), Neer, Paul L.M.J. van (author), Massaad Mouawad, J.M. (author), de Jong, N. (author), Verweij, M.D. (author), Pertijs, M.A.P. (author)
Transit-time ultrasonic flow meters are widely used in industry to measure fluid flow. In practice ultrasonic flow meters either show a zero-flow error or suffer from a significant random error due to a limited signal-to-noise ratio, requiring a significant amount of averaging to achieve good precision. This work presents a method that minimizes...
journal article 2020
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Verweij, Daniëlle (author)
This study was aimed at developing a design guide for stress reducing healthcare facilities for people with a chronic disease and their caregivers. This study was conducted with literature research, interviews and analyzing reference projects. The results of the literature research show the impact of stress on the different users, the importance...
master thesis 2019
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van Willigen, D.M. (author), Mozaffarzadeh, M. (author), Noothout, E.C. (author), Verweij, M.D. (author), de Jong, N. (author), Pertijs, M.A.P. (author), Daeichin, V. (author)
This paper presents the integration steps towards a prototype forward-looking intra-vascular ultrasound probe. An ASIC (Application Specific Integrated Circuit) is laser cut to create a 1.6mm circular shaped die that can be integrated at the tip of a small catheter. The ASIC is designed such that it can be used to transmit and receive on 64...
conference paper 2019
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Sabbadini, A. (author), Caenen, A.F.M. (author), Vos, H.J. (author), de Jong, N. (author), Verweij, M.D. (author)
Shear Wave Elastography (SWE) has been proposed to investigate cardiac health by non-invasively monitoring tissue stiffness. Previous work has shown that the plate-like geometry of the Interventricular Septum (IVS) may result in a dispersion similar to Lamb waves, complicating the link between shear wave speed and cardiac stiffness. However, the...
journal article 2019
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Soozande, Mehdi (author), Ossenkoppele, B.W. (author), Hopf, Y.M. (author), Pertijs, M.A.P. (author), Verweij, M.D. (author), Vos, H.J. (author), Bosch, J.G. (author), de Jong, N. (author)
poster 2019
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Waasdorp, R. (author), Mugge, W. (author), Vos, H.J. (author), de Groot, J.H. (author), de Jong, N. (author), Verweij, M.D. (author), Schouten, A.C. (author), Daeichin, V. (author)
Current methods to track the progression and evaluate treatment of muscular dystrophies are scarce. The electromechanical delay (EMD), defined as the time lag from muscle electrical activity to motion onset, has been proposed as a biomarker, but provides only limited insight in the pathophysiol-ogy of muscle function. This work proposes and...
conference paper 2019
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Massaad Mouawad, J.M. (author), van Willigen, D.M. (author), van Neer, P.L.M.J. (author), de Jong, N. (author), Pertijs, M.A.P. (author), Verweij, M.D. (author)
Current ultrasonic clamp-on flow meters are based on single-element transducers that require manual calibration by aligning these to a fixed acoustic path. Moreover, the size and operational frequency of the transducers cannot be adapted to the parameters of the pipe and the liquid, which are in practice not precisely known a priory. A set of...
conference paper 2019
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Fool, F. (author), Vos, H.J. (author), Shabanimotlagh, M. (author), Soozande, M. (author), Mozaffarzadeh, M. (author), Kim, T. (author), Kang, E. (author), Pertijs, M.A.P. (author), de Jong, N. (author), Verweij, M.D. (author)
To accurately investigate the state of the carotid artery by the local haemodynamics and motion of the plaque using ultrasound, high-frame rate volumetric imaging is necessary. We have specifically designed a matrix array for this purpose. In this proceeding we will focus on imaging a volumetric flow profile using this matrix. For this...
conference paper 2019
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Mozaffarzadeh, M. (author), Minonzio, C.G. (author), Verweij, M.D. (author), Hemm, Simone (author), Daeichin, V. (author)
Phase aberration of focused ultrasound by tissue structure causes focus degradation and reduces the quality of B-mode images. Refraction at the boundary between subcutaneous fat and muscle is one of the dominant factors behind such degradation. To correct this, we propose a refraction compensation method in which ultrasound is transmitted and...
conference paper 2019
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