PROBABILITY DENSITY FUNCTIONS OF TIDAL ELEVATION DATA AND TIDAL/NON-TIDAL COMPONENTS DATA
Double-peak (bi-modal) normal distribution function having four parameters was suggested as the probability density function (hereafter pdf) of tidal elevation data in Korean coastal zone. Frequency distribution analysis were carried out using hourly tidal elevation data of the major ten tidal gauging stations, i.e., Incheon, Gunsan, Mokpo, Jeju, Yeosu, Masan, Gadeokdo, Busan, Pohang, and Sokcho that could be downloaded through the Internet Homepage by the National Ocean Research Institute (NORI). Based on the RMS error and R 2 value comparison analysis, it was found that this suggested function as the pdf of tidal elevation data was found to be more appropriate than the normal distribution function widely used for convenience. The parameters of the double-peak function were estimated optimally using Levenberg-Marquardt method that was modified from the Newton method. The estimated parameters were highly correlated with the non-tidal constants of the tidal gauging stations. Tidal elevation data can be decomposed as the astronomical (tidal) and meteorological (non-tidal, residual) components by the harmonic analysis. The pdf of the tidal component data is obtained by the numerical integration because the data is explicitly expressed by the linear combination of the harmonic functions. However, the distribution of the non-tidal (residual) components which generally show the slightly skewed single-peak shape are also well fitted the double-peak type function suggested in this research, even though the shape of its distribution is very similar to the normal distribution. In the future, the non-Gaussian distribution functions more suitable for the non-tidal components should be tested in detail because the double-peak pdf is basically bi-modal distribution not single-peak distribution.
Hong Yeon Cho Beom Jun Cho Shin Taek Jeong
Coastal Development Research Department, Korea Ocean R&D Institute, ANSAN PO Box 29, Seoul, 425-600, Department of the Civil Engineering, Wonkwang University, Korea
国际会议
第四届亚太地区海岸会议(the Fourth International Conference on Asian and Pacific Coasts)
南京
英文
2007-09-21（万方平台首次上网日期，不代表论文的发表时间）