n.圖心；矩心；重心

A self-adaptive feature extraction method based on power spectral centroid is proposed. 摘要提出一種基于功率譜重心的自適應(yīng)特征信息提取方法。

If this load centroid is behind the elastic axis of the wing structure, then a nose-down twist of the main wing surface results. 如果該載荷重心在機翼結(jié)構(gòu)彈性軸之后，則引起主機翼表面前端向下的扭轉(zhuǎn)。