传统的粗糙集理论只能对数据库中的离散属性进行处理，所以对存在连续属性的数据库必须进行离散化处理。

The traditional rough set theory can only deal with the discrete attribute in a database, so it is necessary to deal with the consistent attribute when the consistent attributes exist in a database.

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由于求解该离散对数的难度与求解乘法群上的离散对数的难度相同，所以在椭圆曲线上可构造出相对安全的密码系统。

Because computing the discrete logarithm more difficulty than the discrete logarithm over multiplication group, so it is possible to construct quite safe cryptosystem.

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