Searched for: subject%3A%22Microphones%22
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Moriaux, Olivier (author)
Unsteady surface pressures shed light on the turbulent structures of boundary layer flow, which dictate for a large part the aerodynamic and aeroacoustic performance of aerodynamic bodies submersed in a flow. Remote microphone probes (RMP), e.g., pinhole probes, provide advantages compared to flush-mounted probes because of their reduced sensing...
master thesis 2023
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Makaveev, Momchil (author)
This project proposes and evaluates a novel concept for an airspeed instrument aimed at small hybrid unmanned aerial vehicles. The working principle is to relate the power spectra of the wall-pressure fluctuations beneath the turbulent boundary layer formed over the vehicle’s body to its airspeed. The instrument consists of two microphones,...
master thesis 2023
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Li, L. (author), Martinez, Jorge (author), Hendriks, R.C. (author)
Estimation of the acoustic-scene related parameters such as relative transfer functions (RTFs) from source to microphones, source power spectral densities (PSDs) and PSDs of the late reverberation is essential and also challenging. Existing maximum likelihood estimators typically consider only subsets of these parameters and use each time frame...
journal article 2023
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Makaveev, M.K. (author), Snellen, M. (author), Smeur, E.J.J. (author)
This paper puts forward a novel design for an airspeed instrument aimed at small fixed-wing tail-sitter unmanned aerial vehicles. The working principle is to relate the power spectra of the wall-pressure fluctuations beneath the turbulent boundary layer present over the vehicle’s body in flight to its airspeed. The instrument consists of two...
journal article 2023
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Pezone, R. (author), Baglioni, G. (author), Sarro, Pasqualina M (author), Steeneken, P.G. (author), Vollebregt, S. (author)
A repeatable method to fabricate multi-layer graphene (ML-gr) membranes of 2r = 85 – 155 μm (t < 10 nm) with a 100% yield on 100 mm wafers is demonstrated. These membranes show higher sensitivity than a commercial MEMS-Mic combined with an area reduction of 10x. The process overcomes one of the main limitations when integrating graphene...
conference paper 2023
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Luesutthiviboon, S. (author)
Nowadays, large wind turbines are installed and operated close to densely populated areas due to the growing need for renewable energy. Noise constraints are hampering this development. The most relevant wind turbine noise source is the so-called Turbulent Boundary Layer Trailing-Edge (TBL–TE) noise. Many passive TBL–TE noise reduction...
doctoral thesis 2022
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Di Paola, Leonardo (author)
The evolution of microphone technology can be linked to the growing multimedia and communication market. The first is linked to the music and audiovisual industry, while the latter is linked to smartphones, smart mobility, and home automation. In all of these audio applications, the common trend is toward downsizing and performance improvement....
master thesis 2022
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Roest, Tobias (author)
Public address (PA) systems are an integral part of every building. Their function as a safety and security system could benefit from adding recording capabilities. With such capabilities, people could be located during evacuation or announcements could be adjusted to room acoustics for better intelligibility. However, adding microphones to a PA...
master thesis 2022
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von den Hoff, B. (author), Merino Martinez, R. (author), Simons, D.G. (author), Snellen, M. (author)
Complex acoustic systems typically present three-dimensional distributions of noise sources. Conventional acoustic imaging methods with planar microphone arrays are unsuitable for three-dimensional acoustic imaging, given the computational demands and the incapability to explicitly account for the presence of multiple sources. This paper...
journal article 2022
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von den Hoff, B. (author), Simons, D.G. (author), Snellen, M. (author)
Full-scale propeller measurements are useful to study the total noise contribution of a propeller-driven aircraft, including installation effects. Full-scale measurements under operational conditions also provide an accurate validation opportunity for propeller noise prediction models. These studies are, therefore, necessary to quantify and...
conference paper 2022
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Pezone, R. (author), Baglioni, G. (author), Sarro, Pasqualina M (author), Steeneken, P.G. (author), Vollebregt, S. (author)
During the past decades micro-electromechanical microphones have largely taken over the market for portable devices, being produced in volumes of billions yearly. Because performance of current devices is near the physical limits, further miniaturization and improvement of microphones for mobile devices poses a major challenge that requires...
journal article 2022
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Chen, Hang (author), Zhou, Hengshun (author), Du, Jun (author), Lee, Chin-Hui (author), Chen, Jingdong (author), Watanabe, Shinji (author), Siniscalchi, Sabato Marco (author), Scharenborg, O.E. (author), Liu, Di-Yuan (author)
In this paper we discuss the rational of the Multi-model Information based Speech Processing (MISP) Challenge, and provide a detailed description of the data recorded, the two evaluation tasks and the corresponding baselines, followed by a summary of submitted systems and evaluation results. The MISP Challenge aims at tack-ling speech processing...
conference paper 2022
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Li, L. (author), Martinez, Jorge (author), Hendriks, R.C. (author)
Many multi-microphone algorithms depend on knowing the relative acoustic transfer functions (RTFs) of the individual sound sources in the acoustic scene. However, accurate joint RTF estimation for multiple sources is a challenging problem. Existing methods to jointly estimate the RTF for multiple sources have either no satisfying performance, or...
conference paper 2022
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Vieira, A.E. (author), von den Hoff, B. (author), Snellen, M. (author), Simons, D.G. (author)
The contribution of the engine and the airframe to the total noise generated by an aircraft varies with the operating conditions. Semi-empirical models are able to account for such variations but require detailed engine and airframe data as input that is not readily available for most aircraft types and operations. This hinders the validation of...
journal article 2022
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Schoorl, Daan (author)
The past years there has been a significant increase in the popularity and commercial availability of consumer drones.
master thesis 2021
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Schulz, Yannick (author)
Driving is a challenging task. When people operate vehicles they utilize all their senses to assess the current traffic scenario and determine appropriate actions to take. Sensors in autonomous driving applications aim to mimic those human senses to build a similar understanding of these complex circumstances. Most scientific attention in the...
master thesis 2021
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Lima Pereira, L.T. (author), Merino Martinez, R. (author), Ragni, D. (author), Gómez-Ariza, David (author), Snellen, M. (author)
This paper explores the advantages of combining asynchronous microphone array measurements for acoustic source mapping in two and three–dimensional applications. Four different approaches are considered, three consisting of the combination of the source maps (arithmetic mean, geometric mean, and minimum value), and a fourth one obtained by...
journal article 2021
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VanDercreek, Colin (author), Merino Martinez, R. (author), Sijtsma, P. (author), Snellen, M. (author)
Aeroacoustic measurements performed by flush-mounted microphone arrays on the walls of closed-section wind tunnels are contaminated by the hydrodynamic pressure fluctuations of the wall's boundary layer. This study evaluates three different microphone cavity geometries for mitigating this issue. Their improvement to the signal-to-noise ratio ...
journal article 2021
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Merino Martinez, R. (author), Rubio Carpio, A. (author), Lima Pereira, L.T. (author), van Herk, S.W.L. (author), Avallone, F. (author), Ragni, D. (author), Kotsonis, M. (author)
The newly refurbished vertical tunnel (V-tunnel) at Delft University of Technology has been redesigned as a state-of-the-art facility for research in aeroacoustics (A-tunnel), as well as fundamental studies in laminar-turbulent transition and flow control. This manuscript focuses on the design and refurbishment aspects of the facility,...
journal article 2020
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Kotti, Sofia Eirini (author), Heusdens, R. (author), Hendriks, R.C. (author)
The use of wireless acoustic sensor networks (WASNs) has received increased attention over the last decade. The advantages of WASNs over stand-alone multi-microphone devices are that the microphone array is not anymore limited by the dimensions of a single device, and that microphones can be placed at arbitrary locations. One of the...
conference paper 2020
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