Results 21 to 30 of about 514,003 (233)
Moth wings are acoustic metamaterials [PDF]
Proceedings of the National Academy of Sciences, 2020 Significance Bats and moths are embroiled in an evolutionary arms race. Using ultrasonic biosonar, bats detect their insect prey, which in turn deploy diverse strategies to avoid predation. Here, we show that some moth species evolved wings covered with a canopy of scales that reduces ultrasonic echoes.
Thomas R. Neil +4 more
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Physics Today, 2016 By incorporating novel subwavelength structures into macroscopic materials, acousticians can create devices with exotic sound-altering properties.
Michael R. Haberman, Matthew D. Guild
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Low-frequency sound absorption performance of composite acoustic metamaterials with rotational labyrinth channels and micro-perforated panels [PDF]
AIP AdvancesIn this paper, a kind of novel acoustic metamaterial combined with a rotational labyrinth and a micro-perforated plate is designed. The design of the rotational labyrinth structure combined with micro-perforated plates endows the acoustic metamaterial ...
Xinxin Liu +4 more
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Retrieving effective acoustic impedance and refractive index for size mismatch samples
AIP Advances, 2022 In this paper, we have presented an analytical solution to extract the effective properties of acoustic metamaterials from the measured complex transmission and reflection coefficients when the metamaterial and impedance tube have different sizes.
Mohammad Javad Khodaei +3 more
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Time-domain imaging of gigahertz surface waves on an acoustic metamaterial
New Journal of Physics, 2018 We extend time-domain imaging in acoustic metamaterials to gigahertz frequencies. Using a sample consisting of a regular array of ∼1 μ m diameter silica microspheres forming a two-dimensional triangular lattice on a substrate, we implement an ultrafast ...
Paul H Otsuka +9 more
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A study on acoustic metamaterial to control reflection sound
Nihon Kikai Gakkai ronbunshu, 2017 Acoustic metamaterial can have arbitrary acoustic characteristics , and there is possibility to improve acoustic performance of any products dramatically. As metamaterial, many kind of types have been propounded and studied.
Yukihide NAGAYO +2 more
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Cylindrical Resonator Sectorally Filled With DNG Metamaterial and Excited by a Line Source [PDF]
, 2012 A circular cylindrical resonator with metallic walls is analyzed in the phasor domain. The resonator contains a wedge of double-negative (DNG) metamaterial that is anti-isorefractive to the double-positive (DPS) material filling the remaining volume of ...
Graglia, Roberto +4 more
core +1 more source
Metamaterials for simultaneous acoustic and elastic bandgaps
Scientific Reports, 2021 In this work, we present a single low-profile metamaterial that provides bandgaps of acoustic and elastic waves at the same time. This was done by ensuring impedance mismatch in two different domains, the fluid domain where the acoustic waves propagate ...
Waiel Elmadih +2 more
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Double-negative acoustic metamaterial [PDF]
Physical Review E, 2004 We show here the existence of acoustic metamaterial, in which both the effective density and bulk modulus are simultaneously negative, in the true and strict sense of an effective medium. Our double-negative acoustic system is an acoustic analogue of Veselago's medium in electromagnetism, and shares many unique consequences, such as negative refractive
Li, Jensen Tsan Hang, Chan, Che Ting
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Acoustic metamaterials with coupled local resonators for broadband vibration suppression
AIP Advances, 2017 This paper investigates a modified acoustic metamaterial system with local resonators coupled through linear springs. The proposed acoustic metamaterial system can provide three band gaps for broadband vibration suppression.
Guobiao Hu +4 more
doaj +1 more source