理学 3D打印中的几何计算 释 fused deposition modeling; FDM 支撑结构的计算与优化 熔融沉积式打印机（fused deposition modeling，FDM）由于价格低廉、操作简单而具有较高的普及程度。但其最大的缺点是无法直接打印模型中的悬空部位。这时往往需要用户在切片之前给悬空部分添加支撑结构，将支撑结构连同模型一起被打印，并在结束后人为去除。
网络与数据通信 协议体系与组成结构 释文 frequency division multiplexing, FDM 频分多路复用
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