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Zhang, H. (author)This thesis describes the analysis, design, prototype implementation, and measurement results of high-performance Class-D amplifiers (CDAs) for audio applications.doctoral thesis 2024
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Zhang, H. (author)In recent decades, dielectric lens antennas have been more and more adopted and developed for sensing and imaging applications at sub-millimeter (sub-mm) wavelengths because they can achieve high gain while keeping their physical size and weight acceptable at these wavelengths. More recently, as low-loss and low-cost lens materials have become...doctoral thesis 2024
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Gül, Önder (author), Zhang, H. (author), Bommer, J.D.S. (author), de Moor, M.W.A. (author), Car, Diana (author), Plissard, Sébastien R. (author), Bakkers, E.P.A.M. (author), Geresdi, A. (author), Kouwenhoven, Leo P. (author)Correction to: Nature Nanotechnologyhttps://doi.org/10.1038/s41565-017-0032-8, published online 15 January 2018. The Letter reports Majorana signatures in hybrid InSb semiconductor nanowire–NbTiN superconductor devices. The devices exhibit a conductance plateau near the conductance quantum 2e<sup>2</sup>/h at bias voltages above the...journal article 2024
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Fiorellini Bernardis, A. (author), Sberna, P.M. (author), Bueno Lopez, J. (author), Zhang, H. (author), Llombart, Nuria (author), Neto, A. (author)Drude's description of the response of low-temperature gallium arsenide to optical pulse excitation is used to evaluate the components of a time-domain Norton equivalent circuit of a photoconductive antenna (PCA) source. The saturation of the terahertz (THz) radiated power occurring at large optical excitation levels was previously associated...journal article 2023
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Zhang, H. (author), Berkhout, Marco (author), Makinwa, K.A.A. (author), Fan, Q. (author)Class-D amplifiers (CDAs) are widely used in audio applications where a high power efficiency is required. As most audio sources are digital nowadays, implementing digital-input CDAs results in higher levels of integration and lower cost. However, prior open-loop digital-input CDAs suffer from high jitter sensitivity and output-stage...conference paper 2023
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Zhang, H. (author), Dabironezare, Shahab Oddin (author), Baselmans, J.J.A. (author), Llombart, Nuria (author)Large format focal plane arrays (FPAs) of dielectric lenses are promising candidates for wide field-of-view submillimeter imagers. In this work, we optimize the scanning gain of such imagers via shaping lens surfaces. We develop an optimization procedure using a field correlation technique between the fields generated by a reflector on the...journal article 2023
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Zhang, H. (author), Jin, Zuquan (author), Jiang, Nengdong (author), Ge, Zhi (author), Schlangen, E. (author), Ling, Yifeng (author), Šavija, B. (author), Wang, Zheng (author)The classically lattice model assumes the local elements behave elastic brittle, neglecting the ductility of the mortar matrix. This leads to the simulated load⁃displacement response more brittle than the realistic. To solve the aforementioned issue, a piece⁃wise approach was introduced to describe the elastic⁃plastic constitutive relation of...journal article 2023
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Chen, Minggang (author), Zhang, H. (author), Fan, Q. (author)Silicon MOSFETs-based medium-power (< 50W) Class-D amplifiers (CDAs) switching in the MHz range have gained popularity in recent years, which achieves better linearity thanks to a higher loop gain in the audio band while enabling the use of LC filters with higher cut-off frequencies. However, for high-power (>100 W) CDAs, such switching...conference paper 2023
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Zhang, H. (author), Nijhuis, S. (author), Newton, C.E.L. (author)Existing studies indicate that a direct view of aquatic elements benefits well-being, and houses with blue views are often associated with higher prices. Therefore, developing analysis and design methods for visibility research of blue spaces are crucial to advance spatial design practice. Especially digital methods for analysing blue visibility...journal article 2023
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Bueno Lopez, J. (author), Sberna, P.M. (author), Fiorellini Bernardis, A. (author), Zhang, H. (author), Neto, A. (author), Llombart, Nuria (author)State-of-the-art THz pulsed commercial systems operating over large bandwidth suffer from high dispersion or low radiation efficiency due to the poor coupling between the transmitter and receiver photoconductive antennas (PCAs). In this work, we present the fabrication and characterization of a leaky-lens PCA that has the potential to solve...journal article 2023
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Zhang, H. (author), Nijhuis, S. (author), Newton, C.E.L. (author)Water, a vital element of human existence, shapes cities and benefits human health through daily exposure. This study delves into advanced digital methods to describe blue space exposure effectively, aiming to optimise spatial accessibility and visibility of water for designing sustainable healthy urban environments. Rotterdam is utilised as a...journal article 2023
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Karmakar, S. (author), Zhang, H. (author), Berkhout, Marco (author), Fan, Q. (author)This paper presents a Class-D piezoelectric speaker driver that employs a quadrature feedback chopping scheme (QCS). Compared to a conventional single feedback chopping scheme (SCS), the use of QCS can eliminate the timing skew between low-voltage (LV) and high-voltage (HV) choppers, greatly improving large-signal linearity. A prototype...conference paper 2023
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Zhang, H. (author), Berkhout, M. (author), Makinwa, K.A.A. (author), Fan, Q. (author)This article presents a digital-input class-D amplifier (CDA) achieving high dynamic range (DR) by employing a chopped capacitive feedback network and a capacitive digital-to-analog converter (DAC). Compared with conventional resistive-feedback CDAs driven by resistive or current-steering DACs, the proposed architecture eliminates the noise...journal article 2023
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Zhang, H. (author), Bueno Lopez, J. (author), Sberna, P.M. (author), Llombart, Nuria (author), Neto, A. (author)Photoconductive antennas (PCAs) are promising candidates for sensing and imaging systems. We have investigated their properties under pulsed laser illumination both in transmission and reception. First, a transmitting PCA has been characterized including a power measurement. Then, a Quasi-Optical (QO) link between a transmitter and a receiver...conference paper 2023
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Zhang, H. (author), Dabironezare, Shahab Oddin (author), Llombart, Nuria (author)Lens based focal plane arrays (FPAs) with thousand elements are promising candidates for wide scanning sub-millimeter security imaging systems. To analyze such arrays, a field correlation approach is employed to design an FPA of quartz lenses coupled to a reflector. We consider quartz as the lens material due to its lower cost compared to...conference paper 2023
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Zhang, H. (author)With the attempt to reduce traffic noise, porous asphalt (PA) mixture is widely used as a wearing course on the highways in the Netherlands. However, due to the open structure, PA mix pavement easily suffers from the loss of individual aggregates from its surface, which is named as ravelling. After the initial ravelling, the damage can rapidly...doctoral thesis 2022
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Zhang, H. (author), Berkhout, Marco (author), Makinwa, K.A.A. (author), Fan, Q. (author)Class-D audio amplifiers produce electromagnetic interference (EMI), which often needs to be suppressed by an external LC filter. However, due to component nonlinearity, this filter can itself cause significant distortion. This article presents a class-D amplifier that suppresses LC filter nonlinearity by 49 dB and is robust to ±30%...journal article 2022
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Zhang, H. (author), Rozsa, N.N.M. (author), Berkhout, Marco (author), Fan, Q. (author)The power supply rejection ratio (PSRR) of conventional differential closed-loop Class-D amplifiers is limited by the feedback and input resistor mismatch and finite common-mode rejection ratio (CMRR) of the operational transconductance amplifier (OTA) in the first integrator. This article presents a 14.4-V Class-D amplifier employing...journal article 2022
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Zhang, H. (author), Nijhuis, S. (author), Newton, C.E.L. (author)Water is a critical element of human existence and has shaped cities for centuries. In urban environments, water provides multiple ecosystem services and is an important element in the design of urban environments. Next to the many qualities and services provided by water, recent research indicates that exposure to freshwater blue space also...review 2022
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ZHANG, H. (author), Fu, Rui (author), Wang, Chang (author), Guo, Yingshi (author), Yuan, W. (author)Vehicle-to-Infrastructure (V2I) communication has provided a solution for the improvement of the traffic efficiency of smart city intersections. For example, turning maneuvers prediction at signalized intersections in a connected environment helps traffic command centers time traffic lights and dynamically predict traffic flow. However, the...journal article 2022