| 摘要 |
<p>The preformed concave bottom (51) of the fold-open goblet, made from a folded rectangular semi-rigid sheet with both halves being superimposed, is a dihedron delimited by the surfaces of two isosceles triangles inscribed within two right isosceles triangles while having a common base and apexes, while a semi-rigid thin lateral strip (36) forming a polygon for supporting the goblet is secured about the gobelet's base when it is unfolded.</p> |
