Visual Demonstration of Tidal Movement with Clear Cycles by Time Frequency Analysis |
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| Sumitoshi Ogata, Takahiro Kawakami, Kenta Kirimoto |
- Abstract:
- The present study deals with tidal movement in a Japanese coastal area where the half day and one day tidal periods are generally observed. We aim to make the dynamics of this tidal movement much clearer from a point of view of time frequency analysis using a short time Fourier transform(STFT) and a wavelet transform(WT) in addition to a conventional fast Fourier transform(FFT). These three approaches are complementary each other and available for the comprehensive understandings of complicated, oceanic phenomena. The STFT analysis reveals that the four tidal periods are observed only when the tidal power becomes relatively weak around every low tide. On the other hand, two of four periods become indiscriminating around every high tide due to a masking effect of the major, strong tidal powers. We also demonstrate that the WT analysis is exclusively available for visualizing the phase shift process of these two major tidal periods.
- Download:
- IMEKO-TC4-2005-044.pdf
- DOI:
- -
- Event details
- IMEKO TC:
- TC4
- Event name:
- TC4 Workshop 2005
- Title:
10th IMEKO TC4 International Workshop on ADC Modelling and Testing - IWADC (together with XIVth IMEKO TC4 International Symposium on New Technologies in Measurement and Instrumentation)
- Place:
- Gdynia/Jurata, POLAND
- Time:
- 12 September 2005 - 15 September 2005