Geometric designs were popular wall decorations in the 14th century.14世纪，几何图形是风靡一时的墙壁装饰图案。Many pictures have been based on simple geometric designs.许多画都是基于简单的几何图案。These results parallel Archimedes'geometric theorems...
Keywords: geometric nonlinearity, sag effect, equivalent modulus of elasticity, vehicle - bridge interaction.关键词: 几何非线性 、 中垂效应 、 等效弹性系数 、 车桥互制.The eigenfrequency of oscillation cavity is the function of cavity's geo...