from keras.models import Sequential
from keras.layers.core import Dense, Dropout, Activation

model = Sequential()
model.add(Dense(512, input_shape=(784,))) # 입력 784, 출력 512
model.add(Activation('relu'))
model.add(Dropout(0.2))
model.add(Dense(512)) # 입력 512(이전 레이어 입력), 출력 512
model.add(Activation('relu'))
model.add(Dropout(0.2))
model.add(Dense(10)) # 입력 512, 출력 10
model.add(Activation('softmax'))