The thead element has a single child node, tr, with three children - all th elements.
thead元素只有一个子节点tr，后者有三个子节点—所有th元素。
2
Usually the numerical manifold method (NMM) is based on meshes of three - or four-nodeelement.
数值流形方法常基于有限元法三结点或四结点单元。
3
The three-node beam element tangent stiffness matrix including the geometric stiffness matrix is developed according to the nonlinear finite element theory.