2023-02-03T04:48:00Z
https://u-ryukyu.repo.nii.ac.jp/oai
oai:u-ryukyu.repo.nii.ac.jp:02002164
2022-02-14T21:27:47Z
1642837622505:1642837855274:1642837871473
1642838403551:1642838406845
バリ島サヌール海岸における波浪特性
Characteristics of Sea Waves at Sanur Coral Beach in Bali
筒井, 茂明
大城, 真一
鈴山, 勝之
Tsutsui, Shigeaki
Oshiro, Shinichi
Suzuyuma, Katsuyuki
Wave statistics
Probability density function
Wave breaking
Coral beach
Beach erosion is a major problem at coral beaches in Bali, Indonesia, because of the changes in natural environment and utilization of coastal areas. Survey of sea waves, as joint research works between Japan and Indonesia, was carried out at Sanur beach in Bali, to know what kinds of waves are effective for beach processes. Features of sea waves and their statistic properties, such as shape moduli of the probability density function and the correlation coefficient between wave heights and periods, are investigated by using the data measured. The results are summarized as follows:\nGeneral features;\n(1) At Sanur beach the wave direction is unchanged throughout the year, and waves in the dry season (June to August) govern the coastal process and sand movement because of higher wave heights and longer wave periods rather than that in the wet season (December to February).\n(2) Swell with the period of about 15 seconds, though dissipated by wave breaking at the top of the coral reef, is significant among wave components penetrating onto Sanur beach.\nWave statistic properties;\n(1) Both in and out the coral reef at high tidal level of water, the probability density function for wave heights is described with the Rayleigh distribution.\n(2) The relations among the shape modulus for wave periods, the correlation coefficient between wave heights and periods, and the spectral width parameter agree, for incident waves, with the results of Goda (1970) and Kimura (1978). Because of wave breaking, however, the shape modulus for wave periods on the coral flat takes smaller values than that for non-breaking waves, and the spectral width becomes wide.\n(3) The correlation coefficient between wave heights and periods increases with respect to the spectral width and, as it tends to unity, the shape modulus for wave periods decreases down to 2.
紀要論文
http://purl.org/coar/resource_type/c_6501
琉球大学工学部
VoR
http://hdl.handle.net/20.500.12000/2215
0389-102X
AN0025048X
琉球大学工学部紀要
49
38
27
jpn
open access