Based on the geometry characteristics of Bertrand surfaces, the complicated surface conjugation issue can be discussed with their directrix line. 基于白川德曲面的幾何特征，將復雜的曲面共軛問(wèn)題歸結到準線(xiàn)上來(lái)討論。
The surface generated by a straight line,the generator,passing through a fixed point,the vertex,and moving along a fixed curve,the directrix. 錐面由一條直線(xiàn)，即母線(xiàn)，通過(guò)一固定點(diǎn)，即頂點(diǎn)，沿一給定曲線(xiàn)，即準線(xiàn)，連續移動(dòng)而產(chǎn)生的平面。
Based on the geometry characteristics of Bertrand surfaces, the complicated surface conjugation issue can be discussed with their directrix line. 基于白川德曲面的幾何特征，將復雜的曲面共軛問(wèn)題歸結到準線(xiàn)上來(lái)討論。
The surface generated by a straight line,the generator,passing through a fixed point,the vertex,and moving along a fixed curve,the directrix. 錐面由一條直線(xiàn)，即母線(xiàn)，通過(guò)一固定點(diǎn)，即頂點(diǎn)，沿一給定曲線(xiàn)，即準線(xiàn)，連續移動(dòng)而產(chǎn)生的平面。
