k of Formula 19 in the paper

[Phil-Lin]

Hi, I'd like to ask you a question. In the paper, Formula （8） is converted to Formula (19). What does the k of Formula （19） mean? I don't see a use for k in Formula （19）.
Looking forward to your reply.

[LiQiufu]

In Eq. 19, k is an iterator, which helps to add up the N identical softmax losses. One can replace it using any other symbol.

[zws98]

Eqn. 9 K什么意思，X(i)是Batch中第i个样本，为什么会有多个softmax累加？

[LiQiufu]

Eqn. 9 K什么意思，X(i)是Batch中第i个样本，为什么会有多个softmax累加？

X^(i)是属于第i类（来自于第i个subject的样本）的样本，与batch无直接关系。公式9是从softmax函数数学推导UCE函数的中间一步，没有直观的物理意义