The L F signals are transformed by entropy based on wavelet packet algorithms for best basis selection, and the results are displayed in time- frequency space namely phase plane.

该方法采用基于熵的小波包最佳基选取准则，对局部损伤信号进行自适应小波包分解，将分解结果显示于时—频空间即相平面上。

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Trimmed by multi-control-surfaces is one important method for the joined-wing near-space-long-endurance UAV to improve the L/D, extend loiter time and decrease take-off weight.

采用多控制面配平是联翼布局临近空间长航时无人机提高升阻比、延长航时、降低起飞重量的重要措施。

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