With a hash index you can find a record in a given file in constant time by generating a hash value for the record and then looking up the record in the file based on that hash value.

借助hash索引，可以通过为记录生成一个hash值，然后根据这个hash值在文件中查找该记录，从而在固定的时间内在给定的文件中找到一条记录。

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After reaching a turbulent state, the system continues its evolution which exhibits that the energy spectrum index is not a constant instead of a wide range of changes in time.

模拟中，系统逐渐达到湍流状态，随着系统的不断演化我们发现如下事实：能谱指数随时间并不是不变的，而是在较宽的范围内变动；

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