【摘要】 提出一种基于Hilbert-Huang变换的周期提取方法。对径流序列直接进行变换后,经频率搜索处理得到径流波动频率及其演变过程。通过对黄河上游兰州站径流序列的分析,表明该方法能够真实地描述径流序列的非平稳非线性特性,具有很高的准确性与可行性。更多还原

【Abstract】 A period retrieval method is presented based on Hilbert-Huang conversion.After runoff time series is directly conversed,the runoff fluctuation frequency and its evolution process are obtained by means of frequency search.Runoff time series at Lanzhou meteorological station upstream of the Yellow River is analyzed,and the results indicate that the method based on Hilbert-Huang conversion can not only describe the non-linear and non-stationary characteristics of the runoff,but also have higher accuracy and feasibility.更多还原