摘要
在折纸时可得到折痕,有些平面图形按照某一规则折时形成的无数折痕可以围成椭圆、双曲线、抛物线等曲线。
One can get creases when doing paper folding. Numerous creases formed by some iehnographies , which are folded according to certain rule, can be ellipses, hyperbolas and parabolas etc.
出处
《宁波教育学院学报》
2006年第1期52-54,共3页
Journal of Ningbo Institute of Education
关键词
折痕
曲线
包络
creases
curves
envelop