Searched for: author:"de Jong, N."
(1 - 20 of 20)
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Massaad, J. (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...
conference paper 2019
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Westerveld, W.J. (author), Leinders, S.M. (author), Neer, P.L.M.J. (author), Urbach, H.P. (author), de Jong, N. (author), Verweij, M.D. (author), Rottenberg, X. (author), Rochus, V. (author)
Future applications of ultrasonography in (bio-)medical imaging require ultrasound sensor matrices with small sensitive elements. Promising are opto-mechanical ultrasound sensors (OMUS) based on a silicon photonic ring resonator embedded in a silicon-dioxide acoustical membrane. This work presents new OMUS modelling: acousto-mechanical non...
conference paper 2019
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Ruf, M. (author), IJspeert, M. (author), van Dam, S. (author), de Jong, N. (author), van den Berg, J.H. (author), Evers, G. (author), Hanson, R. (author)
Diamond membrane devices containing optically coherent nitrogen-vacancy (NV) centers are key to enable novel cryogenic experiments such as optical ground-state cooling of hybrid spin-mechanical systems and efficient entanglement distribution in quantum networks. Here, we report on the fabrication of a (3.4 ± 0.2) μm thin, smooth (surface...
article 2019
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de Rooij, M.R. (author), Nijland, T.G. (author), Quist, W.J. (author), de Jong, N. (author)
In 2015 zijn TNO, de TU Delft en de Rijksdienst voor het Cultureel Erfgoed de programmatische samenwerking MonumentenKennis gestart. Deze loopt in eerste instantie voor de periode 2015-2018. Dit document is het jaarverslag van de samenwerking over 2018. Het is in drie gedeelten opgebouwd: eerst wordt een impressie gegeven van de activiteiten,...
report 2019
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Massaad, J. (author), van Neer, P.L.M.J. (author), van Willigen, D. (author), de Jong, N. (author), Pertijs, M. (author), Verweij, M. (author)
Typically, ultrasonic flow meters assume linear wave propagation. Nevertheless, if the transducers of an ultrasonic flow sensor excite a pressure wave with a high amplitude, nonlinear wave propagation effects become significant. The appearance of higher harmonics increases the bandwidth of the received signal, which may potentially lead to a...
conference paper 2018
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Westerveld, W.J. (author), Leinders, S.M. (author), van Neer, P.L.M.J. (author), Snyder, B. (author), Urbach, H.P. (author), de Jong, N. (author), Verweij, M.D. (author), Rottenberg, X. (author), Rochus, V. (author)
Future applications of ultrasonography in (bio-)medical imaging require ultrasound sensor matrices with small sensitive elements. Promising are opto-mechanical ultrasound sensors (OMUS) based on a silicon photonic ring resonator embedded in a silicondioxide acoustical membrane. This work presents new OMUS modelling: acoustomechanical non-linear...
conference paper 2018
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van Willigen, D. (author), van Neer, P.L.M.J. (author), Massaad, J. (author), Verweij, M. (author), de Jong, N. (author), Pertijs, M. (author)
Transit-time ultrasonic flow meters are based on the fundamental idea that the flow is the only non-reciprocal effect between an upstream and downstream measurement. Non-identical transducers can be used in a reciprocal manner if the circuit is made reciprocal. In this paper we analyze the effect of driver- and readout electronics on the zero...
conference paper 2018
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Massaad, J. (author), van Neer, P.L.M.J. (author), van Willigen, D. (author), Pertijs, M. (author), de Jong, N. (author), Verweij, M. (author)
conference paper 2018
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Vos, H.J. (author), van Neer, P.L.M.J. (author), Verweij, M.D. (author), de Jong, N. (author), Volker, A.W.F. (author)
Three-dimensional (3D) high resolution beamforming is made more difficult by high data rates. This can be overcome by two-step imaging approaches such as the synthetic aperture beamforming technique. In this technique the first step significantly reduces the data rate by line-based delay and sum, whereas the second stage recombines the data to a...
conference paper 2015
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Leinders, S.M. (author), Westerveld, W.J. (author), Pozo Torres, J.M. (author), van Neer, P.L.M.J. (author), Snyder, B. (author), O'Brien, P. (author), Urbach, H.P. (author), de Jong, N. (author), Verweij, M.D. (author)
With the increasing use of ultrasonography, especially in medical imaging, novel fabrication techniques together with novel sensor designs are needed to meet the requirements for future applications like three-dimensional intercardiac and intravascular imaging. These applications require arrays of many small elements to selectively record the...
article 2015
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Leinders, S.M. (author), van Dongen, K.W.A. (author), de Jong, N. (author), Verweij, M.D. (author), Westerveld, W.J. (author), Urbach, H.P. (author), van Neer, P.L.M.J. (author), Pozo Torres, J.M. (author)
Several types of ultrasound sensors have been developed and are used in the field of medical imaging. Conventional transducers are made of piezo-electric material and show good practical performance. However, when the piezo-electric elements need to be small (below 100 μm × 100 μm), these transducers face challenges in fabrication as well as the...
conference paper 2014
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Leinders, S.M. (author), van Dongen, K.W.A. (author), de Jong, N. (author), Verweij, M.D. (author), Westerveld, W.J. (author), Urbach, H.P. (author), van Neer, P.L.M.J. (author), Pozo Torres, J.M. (author)
Ultrasound sensors such as piezoelectric transducers and CMUTs are successfully used for medical imaging. However, especially wiring of individual elements is difficult in the fabrication of small piezoelectric arrays, used in, e.g. the field of intravascular imaging. As an alternative, we designed a novel type of ultrasound receiver based on...
conference paper 2013
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Danilouchkine, M.G. (author), van Neer, P.L.M.J. (author), Verweij, M.D. (author), Matte, G.M. (author), Vletter, W.B. (author), van der Steen, A.F.W. (author), de Jong, N. (author)
Second harmonic imaging is currently accepted as the standard in commercial echographic systems. A new imaging technique, coined as superharmonic imaging (SHI), combines the third till the fifth harmonics, arising during nonlinear sound propagation. It could further enhance the resolution and quality of echographic images. To meet the bandwidth...
article 2013
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van Neer, P.L.M.J. (author), Blaak, S. (author), Bosch, J.G. (author), Lancée, C.T. (author), Prins, C. (author), van der Steen, A.F.W. (author), de Jong, N. (author)
Transesophageal echocardiography (TEE) uses the esophagus as an imaging window to the heart. This enables cardiac imaging without interference from the ribs or lungs and allows for higher frequency ultrasound to be used compared with transthoracic echocardiography (TTE). TEE facilitates the successful imaging of obese or elderly patients, where...
article 2012
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van Neer, P.L.M.J. (author), Danilouchkine, M.G. (author), Matte, G.M. (author), van der Steen, A.F.W. (author), de Jong, N. (author)
Tissue second-harmonic imaging is currently the default mode in commercial diagnostic ultrasound systems. A new modality, superharmonic imaging (SHI), combines the third through fifth harmonics originating from nonlinear wave propagation through tissue. SHI could further improve the resolution and quality of echographic images. The...
article 2011
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van Neer, P.M.L.J. (author), Vos, H.J. (author), de Jong, N. (author)
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article 2011
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Matte, G.M. (author), van Neer, P.M.L.J. (author), Danilouchkine, M.G. (author), Huijssen, J. (author), Verweij, M. (author), de Jong, N. (author)
Abstract—Second-harmonic imaging is currently one of the standards in commercial echographic systems for diagnosis, because of its high spatial resolution and low sensitivity to clutter and near-field artifacts. The use of nonlinear phenomena mirrors is a great set of solutions to improve echographic image resolution. To further enhance the...
article 2011
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Vos, H.J. (author), Goertz, D.E. (author), van der Steen, A.F.W. (author), de Jong, N. (author)
This study investigates the use of an acoustic parametric array as a means for microbubble excitation. The excitation wave is generated during propagation in a nonlinear medium of two high-frequency carrier waves, whereby the frequency of the excitation wave is the difference frequency of the carrier waves. Carrier waves of around 10 and 25 MHz...
article 2011
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van Neer, P.L.M.J. (author), Danilouchkine, M.G. (author), Verweij, M.D. (author), Demi, L. (author), Voormolen, M.M. (author), van der Steen, A.F.W. (author), de Jong, N. (author)
In medical ultrasound, fundamental imaging (FI) uses the reflected echoes from the same spectral band as that of the emitted pulse. The transmission frequency determines the trade-off between penetration depth and spatial resolution. Tissue harmonic imaging (THI) employs the second harmonic of the emitted frequency band to construct images....
article 2011
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Dhonukshe-Rutten, R.A.M. (author), Lips, M. (author), de Jong, N. (author), Marijke, J.M.C.A.P. (author), Hiddink, G.J. (author), van Dusseldorp, M. (author), de Groot, L.C.P.G.M. (author), van Staveren, W.A. (author), Centraal Instituut voor Voedingsonderzoek TNO TNO Voeding (author)
Subclinical vitamin B-12 deficiency is common in the elderly. Encouraged by early indications, we investigated the plasma vitamin B-12 status in association with bone mineral content (BMC) and bone mineral density (BMD) in frail elderly people. Data of 194 free-living Dutch frail elderly (143 women and 51 men) were available. BMC and BMD were...
article 2003
Searched for: author:"de Jong, N."
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