In recent years, active noise reduction technology has become a research hotspot. However, most active noise reduction technologies are developed based on passenger vehicles and are not implemented in large commercial vehicles. The large commercial vehicle sound field space is large, the traditional active noise reduction method is difficult to implement.
View Article and Find Full Text PDFSince the connection method at the boundary of the hybrid FE-SEA (finite element-statistical energy analysis, FE-SEA) model affects the overall calculation accuracy of the model, the missing or inaccurate connection relation will lead to a large error in the model calculation. In order to effectively solve the calculation error caused by the connection problem of hybrid FE-SEA model, this paper starts from the modeling methods and connection relations of "hybrid-point" connection, "hybrid-line" connection and "hybrid-surface" connection. In order to solve the modeling method and correction problems of the "hybrid-point" connection in the hybrid FE-SEA model, the "out-of-plane" wave motion equation at the "hybrid-point" connection was established by using the superposition principle of plane waveforms in polar coordinate system.
View Article and Find Full Text PDFThe high morbidity of patients with coronavirus disease 2019 (COVID-19) brings on a panic around the world. COVID-19 is associated with sex bias, immune system, and preexisting chronic diseases. We analyzed the gene expression in patients with COVID-19 and in their microbiota in order to identify potential biomarkers to aid in disease management.
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