大型支撑框筒结构是巨型桁架体系的主要形式之一。

The concept and framework of constructing a support system of territorial science and technology of agriculture;

youdao

大型支撑框筒结构是巨型桁架体系的主要形式之一。

The concept and framework of constructing a support system of territorial science and technology of agriculture;

youdao