Results 51 to 60 of about 1,493,631 (236)
Frontiers in Physics, 2022 We report the numerical and experimental realization of a type of ultrathin planar wall with low-frequency dual-band sound absorption. The proposed planar wall is constructed by a periodic subwavelength unit cell (with a thickness of λ/19) which consists
Yu-wei Xu +10 more
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Bilayer ventilated labyrinthine metasurfaces with high sound absorption and tunable bandwidth
Scientific Reports, 2021 The recent advent of acoustic metamaterials offers unprecedented opportunities for sound controlling in various occasions, whereas it remains a challenge to attain broadband high sound absorption and free air flow simultaneously.
Jiayuan Du +5 more
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Applied Sciences, 2022 The performance of opera and the post-pandemic slow recovery of the public, who have been hesitant to return to frequent attendance of cultural venues, has inspired the authors to analyze the acoustic behavior of the National Theater of Zagreb, by ...
L. Tronchin, A. Bevilacqua
semanticscholar +1 more source
Rainbow reflection and broadband energy absorption of water waves by graded arrays of vertical barriers [PDF]
Journal of Fluid Mechanics, 2021 The rainbow reflection effect describes the broadband spatial separation of wave spectral components caused by a spatially graded array of resonators. Although mainly studied in optics and acoustics, this phenomenon has recently been demonstrated both ...
Ben Wilks, F. Montiel, S. Wakes
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Acoustic absorption of hemp-lime construction [PDF]
Construction and Building Materials, 2016 Abstract Hemp-lime concrete is a sustainable alternative to standard wall construction materials. It boasts excellent hygrothermal properties in part deriving from its porous structure. This paper investigates the acoustic properties of hemp-lime concrete, using binders developed from hydrated lime and pozzolans as well as hydraulic and cementicious ...
Kinnane, Oliver +4 more
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Green Underwater Wireless Communications Using Hybrid Optical-Acoustic Technologies
IEEE Access, 2021 Underwater wireless communication is a rapidly growing field, especially with the recent emergence of technologies such as autonomous underwater vehicles (AUVs) and remotely operated vehicles (ROVs). To support the high-bandwidth applications using these
Kazi Yasin Islam +4 more
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Acoustic absorption of solid foams with thin membranes [PDF]
Applied Physics Letters, 2018 We measured the acoustic absorption, in the 0.5–6 kHz frequency range, of polyurethane foams with mean pore diameters between 0.6 and 3.2 mm. Two types of foams were investigated: classical open-cell ones versus membrane foams, in which thin polyurethane membranes were preserved during solidification.
Gaulon, Camille +8 more
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Sound absorption in Hilbert fractal and coiled acoustic metamaterials [PDF]
Applied Physics Letters, 2022 We describe here a class of acoustic metamaterials with fractal Hilbert space-filling and coiled geometry with equal tortuosity for noise mitigation. Experiments are performed using a four-microphone impedance tube and benchmarked against non-viscous and viscothermal finite element models related to configurations spanning up to five fractal/geometry ...
G. Comandini +4 more
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Design and experimental validation of a finite-size labyrinthine metamaterial for vibro-acoustics: enabling upscaling towards large-scale structures [PDF]
Philosophical TransactionsIn this article, we present the design and experimental validation of a labyrinthine metamaterial for vibro-acoustic applications. Based on a two-dimensional unit cell, different designs of finite-size metamaterial specimens in a sandwich configuration ...
Svenja Hermann +5 more
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Subwavelength total acoustic absorption with degenerate resonators [PDF]
Applied Physics Letters, 2015 We report the experimental realization of perfect sound absorption by sub-wavelength monopole and dipole resonators that exhibit degenerate resonant frequencies. This is achieved through the destructive interference of two resonators' transmission responses, while the matching of their averaged impedances to that of air implies no backscattering ...
Min Yang +5 more
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