J Acoust Soc Am
January 2020
In this paper, the sound transmission loss (STL) of multi-layered infinite micro-perforated plates (MPPs) is studied. A prediction model for the STL of the multi-layered infinite MPPs is developed, where each MPP may or may not have a perforation, and the number of MPPs is arbitrary. When the frequency of interest is well below the critical frequency of the plate such that the effect of flexural vibration can be neglected compared to that of the inertia term, the mass is replaced by an equivalent complex mass.
View Article and Find Full Text PDFRegular inspection for the maintenance of the wind turbines is difficult because of their remote locations. For this reason, condition monitoring systems (CMSs) are typically installed to monitor their health condition. The purpose of this study is to propose a fault detection algorithm for the mechanical parts of the wind turbine.
View Article and Find Full Text PDFIn this paper, the sound transmission loss (STL) of thin double plates with an air cavity between them in a rigid duct is considered using an analytical approach. The vibration motion of the plate and sound pressure field are expanded in terms of an infinite series of the modal functions. Under the plane wave condition, a low frequency solution is derived by including the first few symmetric modes.
View Article and Find Full Text PDFIt was previously reported that in Ras transformed NIH3T3 cells, dynamin II acts as an intermediate messenger in the Ras signal transduction pathway leading to membrane ruffling and cell migration. However, these results do not provide sufficient evidence of a relationship between dynamin II and the Ras signal transduction pathway leading to membrane ruffling and cell migration. The results showed that a dynamin II association with myosin II as a signaling molecule is involved in NIH3T3 cell migration through the Ras/PI3K signaling pathway, and is associated with the p85 subunit of PI3K.
View Article and Find Full Text PDFA theoretical method based on mutual radiation impedance is proposed to compute the sound absorption performance of a Helmholtz resonator array in the low-frequency range. Any configuration of resonator arrangement can be allowed in the method, while all the resonators may or may not be identical. Comparisons of the theoretical predictions with those done by the past studies or experiments show that the present method can accurately predict the absorption performance in more general cases.
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