1.Because the ideal “rigid joint” and “hinged joint” are inexistent, the stiffness of any connection types is between ideal rigid joint and hinged joint.
因为理想的节点铰点是不存在的,任何连形式的度都是介于理想完全铰间的。
2.By using Taylor's formula, the article deduces the sufficient condition of the existent extreme value and the necessary condition of the inexistent extreme value of trinary function.