Message Digests are secure, one-way hash functions that convert arbitrary length data into fixed-length check sum / hash code.

消息摘要是一个安全的、单向的哈希函数，把任意长度的数据转化成固定长度的校验和/哈希码。

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Then it introduces receiving signal as reliability evaluate or weighted coefficient of hard-decision, consequently presents weighted bit-flipping decoding algorithm based on check sum.

在此基础上引入接收信号作为可靠性评估，使评估值作为硬判决的加权系数，从而提出基于校验和的加权位翻转解码算法。

youdao

Then it introduces receiving signal as reliability evaluate or weighted coefficient of hard-decision, consequently presents weighted bit-flipping decoding algorithm based on check sum.

在此基础上引入接收信号作为可靠性评估，使评估值作为硬判决的加权系数，从而提出基于校验和的加权位翻转解码算法。

youdao