U-Net Model Architecture.

U-Net architecture used for the experiments in Table 1. D specifies the base level of channels; we considered experiments with D = 2, 4, 8, 16.用于表1中各项实验的U-Net架构。其中D为通道数的基准基数，本研究开展了D分别取值为2、4、8、16的多组实验。