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The characteristics of nonlinear wave decay over a fluidized bed in coastal waters were investigated by applying the HHT method to analyze the measurements from wave flume experiments. The Ensemble EMD (EEMD) was adopted to decompose the wave and pore pressure data into the intrinsic mod functions (IMF). In a resonantly fluidized response, the results of Hilbert amplitude spectrum of waves derived by the HHT illustrate that wave decay obviously occurs mainly on the fundamental component. In following non-resonantly fluidized tests, the wave decay becomes relaxed with thinner fluidized-layer. Furthermore, the wave decay is immediately due to fluidized response, but the decay along propagation over a fluidized bed is relatively insignificant. The wave-decay ratio is found to be directly proportional to the magnitude of Ursell number (Ur).

In recent years, the impacts of climate change and human activities generate the change of hydrological conditions, leading that the hydrological frequency calculation data don't satisfy the premise of consistency. For the hydrological frequency calculation about inconsistency series, this paper proposed the inconsistency of hydrological frequency calculation method called TFPW-MK-Pettitt and EEMD. First, texting the hydrological series inconsistency used trend-off pre-whitening Mann Kendall-Pettitt methods; Second, the EEMD method was applied to revise uniformity hydrological series; Finally, calculating the hydrological frequency of correcting series. The following conclusions 1) the TFPW-MK-Pettitt method is suitable for our country hydrological series by statistical experiment; 2) the year of 1956 to 2012, runoff series of the Yichang station have downward trend by using the proposed method; 3) the design value of frequency calculation results is smaller 10% than before correction by using the EEMD method.

In order to analyze the effect of engine vibration on cab noise of construction machinery in multi-frequency bands, a new method based on ensemble empirical mode decomposition (EEMD) and spectral correlation analysis is proposed. Firstly, the intrinsic mode functions (IMFs) of vibration and noise signals were obtained by EEMD method, and then the IMFs which have the same frequency bands were selected. Secondly, we calculated the spectral correlation coefficients between the selected IMFs, getting the main frequency bands in which engine vibration has significant impact on cab noise. Thirdly, the dominated frequencies were picked out and analyzed by spectral analysis method. The study result shows that the main frequency bands and dominated frequencies in which engine vibration have serious impact on cab noise can be identified effectively by the proposed method, which provides effective guidance to noise reduction of construction machinery.