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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)Ultrasonic flow meters (UFMs) based on transducer arrays offer several advantages. With electronic beam steering, it is possible to tune the steering angle of the beam for optimal signal-tonoise ratio (SNR) upon reception. Moreover, multiple beams can be generated to propagate through different travel paths, covering a wider section of the flow...article 2022
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Massaad, J. (author), van Neer, P.L.M.J. (author), van Willigen, D.M. (author), Noothout, E.C. (author), de Jong, N. (author), Pertijs, M.A.P. (author), Verweij, M.D. (author)Common clamp-on ultrasonic flow meters consist of two single-element transducers placed on the pipe wall. Flow speed is measured noninvasively, i.e., without interrupting the flow and without perforating the pipe wall, which also minimizes safety risks and avoids pressure drops inside the pipe. However, before metering, the transducers have to...article 2022
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- Massaad, J. (author), van Neer, P.L.M.J. (author), van Willigen, D.M. (author), Sabbadini, A. (author), de Jong, N. (author), Pertijs, M.A.P. (author), Verweij, M.D. (author) article 2022
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- Visschers, F.L.L. (author), Massaad, J. (author), van Neer, P.L.M.J. (author), Verweij, M.D. (author), Liu, D. (author), Broer, D.J. (author) article 2022
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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)Clamp-on ultrasonic flow meters (UFMs) are installed on the outside of the pipe wall. Typically, they consist of two single-element transducers mounted on angled wedges, which are acoustically coupled to the pipe wall. Before flow metering, the transducers are placed at the correct axial position by manually moving one transducer along the pipe...article 2022
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Massaad, J. (author), van Neer, P.L.M.J. (author), van Willigen, D.M. (author), Sabbadini, A. (author), de Jong, N. (author), Pertijs, M.A.P. (author), Verweij, M.D. (author)Current ultrasonic clamp-on flow meters consist of a pair of single-element transducers which are carefully positioned before use. This positioning process consists of manually finding the distance between the transducer elements, along the pipe axis, for which maximum SNR is achieved. This distance depends on the sound speed, thickness and...article 2021
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Lathouwers, S. (author), Everts, M.H. (author), Huisman, M. (author)String sanitizers are widely used functions for preventing injection attacks such as SQL injections and cross-site scripting (XSS). It is therefore crucial that the implementations of such string sanitizers are correct. We present a novel approach to reason about a sanitizer's correctness by automatically generating a model of the implementation...conference paper 2020
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Quesson, B.A.J. (author), van Neer, P.L.M.J. (author), Es, M. (author), M.H. van, (author), Piras, D. (author), Hatakeyama, K. (author), Mohtashami, A. (author), van der Lans, M.J. (author)In Subsurface Scanning Probe Microscopy (SSPM), Atomic Force Microscopy (AFM) is combined with ultrasound. The AFM cantilever is used as a receiver. At low frequencies (O(MHz)) the method can be used to measure the stiffness contrast in a sample and at high frequencies (O(GHz)) to measure scattering based contrast. Both variants use modulated...conference paper 2020
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van Neer, P. (author), Volker, A. (author), Berkhoff, A. (author), Schrama, T. (author), Akkerman, H. (author), van Breemen, A. (author), Peeters, L. (author), van der Steen, J.L. (author), Gelinck, G.H. (author)Ultrasound based mid-air haptic feedback devices can produce tactile sensations at any time and position without restricting human motion. This is useful for augmented and virtual reality, feedback buttons and virtual user interfaces. The haptic feedback mechanism is caused by acoustic radiation force and streaming. Typical solutions to induce...conference paper 2020
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Peters, L.C.J.M. (author), Ollearo, R. (author), Verbeek, R.G.F.A. (author), van der Steen, J.L.P.J. (author), Akkerman, H.B. (author), Volker, A.W.F. (author), van Neer, P.L.M.J. (author), Gelinck, G.H. (author)Large-area flexible ultrasound arrays can offer new ultrasound modalities in multiple fields. The production of these arrays when using CMOS-type fabrication techniques faces scalability challenges and costs increase dramatically when upscaled to large dimensions. We investigate the monolithic production of large-area PPT (Printed Polymer...conference paper 2019
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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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Saeed, A. (author), Volker, A.W.F. (author), Martina, Q. (author), Alalouni, A. (author)Scale and corrosion affect the production certainty of oil and gas well. Scale build-up reduces flow and ultimately could shut down production when it block to tubing completely. Corrosion of the tubing wall occurs very often simultaneously with scale build-up and affects the integrity of the tubing wall. Vital information about the integrity is...conference paper 2019
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Behringer, A. (author), Beerens, S.P. (author), van der Spek, E. (author), Sprik, R. (author)Wideband low frequency transducers are crucial enablers for building underwater communication networks. The use of low frequencies promises long range communication ranges, but most low-frequency transducers are large, lack directionality and have limited bandwidth. The aim of this study is to tackle these limitations. We take a novel approach...conference paper 2019
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van Neer, P.L.M.J. (author), Volker, A.W.F. (author), Berkhoff, A.P. (author), Akkerman, H.B. (author), Schrama, T. (author), van Breemen, A. (author), Gelinck, G.H. (author)Recently, there has been considerable interest in the development of ultrasound based mid-air haptic feedback devices. These devices allow for tactile sensations to be induced at any position and time without constraints to human motion, which is useful for virtual user interfaces, augmented/virtual reality and feedback buttons. The haptic...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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Quesson, B.A.J. (author), van Neer, P.L.M.J. (author), van Riel, M.C.J.M. (author), van Es, M.H. (author), Piras, D. (author), Hatakeyama, K. (author), Mohtashami, A. (author), Navarro, V. (author), Duivenvoorde, T. (author), Sadeghian Marnani, H. (author)Many techniques are under development for the detection of subsurface defects or cracks. One such method is GHz subsurface probe microscopy (GHz SSPM). Here, modulated GHz elastic waves are transmitted through the bottom of a sample. The waves are scattered by buried features and detected using the probe of an atomic force microscope (AFM),...conference paper 2018
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Golliard, J. (author), Belfroid, S.P.C. (author), Vijlbrief, O. (author), Lunde, K. (author)The flow-induced pulsations in corrugated pipes result from a feedback loop between an acoustic resonator and the noise amplification at each shear layer in the axisymmetric cavities forming the corrugations. The quality factor of the resonator is determined by the reflection coefficients at the ends of the corrugated pipe and by the damping in...conference paper 2015
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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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van Zon, A.T. (author), Volker, A.W.F. (author)The concept of predictive maintenance using permanent sensors that monitor the integrity of an installation is an interesting addition to the current method of periodic inspections. Guided wave tomography had been developed to create a map of the wall thickness using the travel times of guided waves. It can be used for both monitoring and for...conference paper 2014
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Volker, A.W.F. (author), van Zon, A.T. (author)The inspection of wall loss corrosion is difficult at pipe supports due to limited accessibility. The recently developed ultrasonic Multi-Skip screening technique is suitable for this problem. The method employs ultrasonic transducers in a pitch-catch geometry positioned on opposite sides of the pipe support. Shear waves are transmitted in the...conference paper 2014