Until now, there is a familiar method of measuring the acoustic materials that is the method of measuring the acoustic absorptivity in the reverberation room. In this paper, the surface acoustic impedance of the new material made from PET is measured by the pulse method in an acoustic pipe, ...
adapt totheimpedancevariations of a configuration, but is targeted as shorter [...] seagate.com seagate.com PCIe 規格也會使用傳輸端 (和接收端) 校準 來配合配置抗阻變化調整,但會當作較 SAS 短 的傳輸通道。 seagate.com seagate.com The cable will carry the video signal from the ...
Consider the transmission of an ultrasonic signal between materials having different acoustic impedance values. Only a part of the signal passes; the rest is reflected. Thus, from the ratio of the incident signal amplitude and the reflected amplitude and the known impedance of one material, the ot...
The specific acoustic impedance is the complex ratio of the effective sound pressure at a point of an acoustic medium or mechanical device to the effective particle velocity at that point. From: Acoustics: Sound Fields and Transducers, 2012 ...
Planar acoustic metamaterials with the active control of acoustic impedance using a piezoelectric composite actuator In the Paper, there are presented methods for a precise active control of the acoustic impedance of large planar structures, e.g glass plates or shells, by... Nováková,Kateřina 被...
We have proved that the density, acoustic phase velocities, and hence the acoustic impedance of the nanocomposite films increase with the alumina content, which gives us another option of tailoring the acoustic impedance of the nano-composite film for making the matching layer of high-frequency ...
of transition metal dichalcogenide (TMD) films was shown to include coherent LA phonons in the frequency range extending up to 1 THz12,13,14,15as the film thicknesses decrease to a few monolayers. The mismatch in acoustic impedance between clamped exfoliated layers and their underlying ...
of the proposed super absorber. The introduction of rubber coating leads to a significant decrease of the effective sound speed in the water channel, resulting in the phenomenon of slow-sound propagation. From the perspective of numerical simulations and acoustic impedance analysis, it is proved ...
As ultrasound pulses traveling in a medium encounter an interface between different materials, the magnitude of the reflected waves will depend on the difference in acoustic impedance of the two materials. The impedance Z is calculated by multiplying the density of the material by the material's sp...
However, general acoustic emission sensors have certain limitations for these materials due to the low acoustic impedances. Kim et al. [101] compared various high sensitivity acoustic emission sensors for glass reinforced plastic to achieve a broadband frequency spectrum. Tang et al. [102] did an...