3节点三角形膜单元
3-node triangular membrane element
6节点三角形单元
6-node triangular element
迹点三角形
triangle of disappearing lines
灭点三角形
triangle of disappearing points
等角三角形命题
equiangular triangleproposition
等腰直角三角形波导
isosceles-right triangular waveguide
等腰直角三角形网
right-triangle irregular network