1)broken top-chord,折线形上弦2)polygonal top-chord,折线形上弦杆3)curved top chord,曲线形上弦杆4)sine polyline,正弦折线5)parabolic chord truss,抛物线形折弦桁架6)retracing cosine curve,余弦折回曲线
用法例句
In this paper,firstly,we according to link line of equally spaced points of on sine function picture,obtained some important properties of sine polyline.