A harmonic analysis for short data series is suggested to check the variation of the sensitivity and phase lag during the tidal observations.

为检验潮汐观测期间灵敏度及相位的变化，提出一种短资料的调和分析方法。

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Using the 10th International geomagnetic Reference Field (IGRF) models, the latitudinal distribution of harmonic amplitude and its time-variation of geomagnetic potential are investigated.

利用第10代国际参考地磁场模型(IGRF)的资料，研究了地磁位的谐波振幅的纬度分布及其时间变化。

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The fluctuation circle of aquatic products price between 1978 and 2000 via ratio of variation and harmonic wave was researched.

采用变异率指标与谐波分析法研究了1978-2000年水产品年度收购价格波动的周期性。

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