Results 1 to 10 of about 2,036,069 (311)
Acoustic transmission loss in Hilbert fractal metamaterials. [PDF]
Sci Rep, 2023 AbstractAcoustic metamaterials are increasingly being considered as a viable technology for sound insulation. Fractal patterns constitute a potentially groundbreaking architecture for acoustic metamaterials. We describe in this work the behaviour of the transmission loss of Hilbert fractal metamaterials used for sound control purposes. The transmission
Comandini G +3 more
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Tunable Fluid-Type Metasurface for Wide-Angle and Multifrequency Water-Air Acoustic Transmission [PDF]
Research, 2021 Efficient acoustic communication across the water-air interface remains a great challenge owing to the extreme acoustic impedance mismatch. Few present acoustic metamaterials can be constructed on the free air-water interface for enhancing the acoustic ...
Zhandong Huang +12 more
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Acoustic Transmission Measurements for Extracting the Mechanical Properties of Complex 3D MEMS Transducers [PDF]
MicromachinesRecent publications on acoustic MEMS transducers present a new three-dimensional folded diaphragm that utilizes buried in-plane vibrating structures to increase the active area from a small chip volume. Characterization of the mechanical properties plays
Dennis Becker +3 more
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Pneumothorax effects on pulmonary acoustic transmission.
J Appl Physiol (1985), 2015 Pneumothorax (PTX) is an abnormal accumulation of air between the lung and the chest wall. It is a relatively common and potentially life-threatening condition encountered in patients who are critically ill or have experienced trauma. Auscultatory signs of PTX include decreased breath sounds during the physical examination.
Mansy HA +6 more
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Directional acoustic transmission based on metamaterials
AIP Advances, 2018 To explore the simple low-loss operation of directional acoustic transmission technology, the propagation of acoustic waves in resonant phononic crystals was studied, and a transmission model based on acoustic metamaterials was constructed.
Shuai Tang, Jianning Han, Tingdun Wen
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Synchronization of Acoustic Signals for Steganographic Transmission [PDF]
Sensors, 2021 Steganography is a technique that makes it possible to hide additional information (payload) in the original signal (cover work). This paper focuses on hiding information in a speech signal. One of the major problems with steganographic systems is ensuring synchronization.
Jaroslaw Wojtun, Zbigniew Piotrowski
openaire +3 more sources
FEM Investigation of a Multi-Neck Helmholtz Resonator
Applied Sciences, 2023 An increasingly significant area of research with several applications in numerous disciplines is that of multi-neck Helmholtz resonators. This research is set to explore the accuracy and applicability of the finite element method (FEM) for the ...
Nikolaos M. Papadakis +1 more
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Bandgap optimization for chiral acoustic metamaterials based on material selection method
Zhongguo Jianchuan Yanjiu, 2023 ObjectivesThis study seeks to expand the bandgap frequency band, reduce the bandgap starting frequency and analyze and optimize the bandgap parameters of acoustic metamaterials.
Luyun CHEN, Xing XIE
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Leakage Effect on the Transmission Properties of a Duct Loaded with a Helmholtz Resonator
Applied Sciences, 2022 The characteristics of transmitted acoustic field have important significance to the leakage detection and the acoustic metasurface technology. When the additional leak holes are present, the conventional single neck Helmholtz resonator will naturally ...
Yang Ou, Yonghui Zhao
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A blind contour‐aware quality model for sonar images
IET Image Processing, 2022 Since the penetration depth of visible light is limited in muddy and dark deep marine environment, sonar imaging, which is independent of natural light, has been attracting much attention in underwater detections.
Weiling Chen +3 more
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