Results 21 to 30 of about 21,616 (265)
Click emission in Dall's porpoise Phocoenoides dalli, focusing on physical properties of tissues. [PDF]
PLoS ONE, 2018 Dall's porpoise (Phocoenoides dalli) is one of most common North Pacific porpoise species, for which information on sound-emitting processes is limited.
Mika Kuroda +5 more
doaj +1 more source
Machines, 2022 In order to apply the nonlinear energy sink (NES) to reduce the low-frequency noise inside a 3D acoustic cavity with an impedance boundary, a two degrees-of-freedom (DOF) dynamic model of the coupled system of one damped acoustic mode of a regular 3D ...
Jianwang Shao +3 more
doaj +1 more source
ResearchImpedance metasurfaces enable accurate regulation of acoustic fields. However, they can hardly supply a flexible response as such perfect operation is accompanied by stringent requirements on the design of unit cells.
Yu-Ze Tian +4 more
doaj +1 more source
Acoustic Impedance Study of Peritubal Myoclonus
Acta Oto-Laryngologica, 2002 An audible clicking sound coexistent with the contractions of the peritubal muscles is thought to be an isolated form of palatal myoclonus that presents with myoclonal contractions of the soft palate, larynx, pharynx and, sometimes, cervicofacial area.
Yetiser, S., Kazkayasi, M., Civitci, D.
openaire +2 more sources
On Wave Impedance and Specific Impedance of Materials in Acoustics [PDF]
The Journal of the Acoustical Society of America, 1956 If impedance is defined as an operator that permits one to go from an “effect” back to a “cause” (in hydrodynamics, from velocity to pressure), it is seen that the impedance field of a wave is constant in the case of a plane wave, but only in this case.
Théodore Vogel, Gaston Laville
openaire +1 more source
Design and experimental evaluation of a travelling wave thermoacoustic engine
Energy Reports, 2020 In a thermoacoustic engine, acoustic impedance plays a key role to improve the system performance. A matching stub is a component which can be applied to adjust the acoustic impedance.
Patcharin Saechan, Isares Dhuchakallaya
doaj +1 more source
Advanced Engineering Materials, EarlyView.This article presents the design, modeling, and characterization of air‐pressure–actuated programmable vibroacoustic metamaterials (PVAMM). The study focuses on leveraging air pressure to dynamically tune resonance frequencies for effective noise attenuation.
William Kaal +2 more
wiley +1 more source
Ultra-Broadband Sound Absorbing Materials Based on Periodic Gradient Impedance Matching
Frontiers in Materials, 2022 Ultra-broadband sound absorption with periodic gradient impedance matching is of great concern in the research of acoustic materials. This study investigates the impedance matching of composite acoustic metamaterials comprising micro-perforated plates ...
Fei Wu +7 more
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Karl Popper and the Mechanisms of Hydrogen Embrittlement
Advanced Engineering Materials, EarlyView.Representation of the beginning of loss of ductility rather than embrittlement. Small concentrations of hydrogen in a diffusible form within iron are well‐established to harm the mechanical integrity of steels. There are theories that attempt to explain the pernicious role of hydrogen.
H. K. D. H. Bhadeshia
wiley +1 more source
Current Status and Challenges in Data Collection for Aerospace Coatings Deposited by Plasma Spraying
Advanced Engineering Materials, EarlyView.An innovative approach has been integrated into the GRENAT project to optimize plasma spraying and coating performance. Raw materials are accelerated and melted in the plasma generated by torches, creating coatings. Monitoring sensors collect process data which are combined with ex situ characterization data.
Lila Randriamananjara +8 more
wiley +1 more source