In the same goaf, there would be an equivalent or approximate equivalent obvious variation period and sustained time.

同一采空区中，不同测点有相等或近似相等的显著变化周期和持续时间。

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The gravimetric observation curves at Chengdu Standard Station showed significantly annual variation period, with air pressure and ground water being main interference factors.

成都基准台的重力观测曲线具明显年变周期，其干扰因素主要为气压和地下水。

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The first phase of the project, which includes three factory buildings, had been completed for a year and had experienced a temperature variation period with good effectiveness.

该工程一期三幢厂房已竣工一年，经历一个温度变化周期的使用，效果良好。

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Response rates were low, which increased random variation from one period to the next.

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The variation in government policy over this time period was remarkable.

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And while they say there can be significant variations in some of these, it seems one of the reasons Brent crude continues to appeal is that there's least variation in its price, at around one US cent per barrel over a long period.

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