Considering the characteristics of large slenderness ratio structure, it is reasonable to simplify the dynamics of a HALE aircraft as the plunge, pitch, and flap motions of a planar airfoil. The ...

Nonlinear optical materials such as silicon can be used to make on-chip devices that break dynamic reciprocity. (Courtesy: K Xia) A new method for making devices that act like a “one-way street” for ...

Modern geopolitics is defined less by steady evolution than by sudden rupture. States that appear stable disintegrate overnight; alliances collapse after decades of endurance; markets, empires, and ...