我正在使用 Keras 训练基于深度 CNN 的神经网络,并且在训练到第 16 个时期时的准确度为 90%。它在第 17 个时期大幅下降到 40%,然后在下一个时期下降到 3%,并保持不变,直到训练结束。可能是什么原因造成的?
这是我的模型架构:
## input layer
input_layer = Input((S, S, L, 1))
## convolutional layers
conv_layer1 = Conv3D(filters=8, kernel_size=(3, 3, 7), activation='relu', padding = 'same')(input_layer)
conv_layer2 = Conv3D(filters=16, kernel_size=(3, 3, 5), activation='relu', padding = 'same')(conv_layer1)
conv_layer3 = Conv3D(filters=32, kernel_size=(3, 3, 3), activation='relu', padding = 'same')(conv_layer2)
print(conv_layer3._keras_shape)
conv3d_shape = conv_layer3._keras_shape
conv_layer3 = Reshape((conv3d_shape[1], conv3d_shape[2], conv3d_shape[3]*conv3d_shape[4]))(conv_layer3)
conv_layer4 = Conv2D(filters=64, kernel_size=(3,3), activation='relu')(conv_layer3)
flatten_layer = Flatten()(conv_layer4)
## fully connected layers
dense_layer1 = Dense(units=256, activation='relu')(flatten_layer)
dense_layer1 = Dropout(0.4)(dense_layer1)
dense_layer2 = Dense(units=128, activation='relu')(dense_layer1)
dense_layer2 = Dropout(0.4)(dense_layer2)
output_layer = Dense(units=output_units, activation='softmax')(dense_layer2)
我将添加培训的截图:
对此,我有两个问题:
答案 0 :(得分:0)