One of the most impressive hydrographic technique developed over the past few decade is multibeam... more One of the most impressive hydrographic technique developed over the past few decade is multibeam sonar systems. Sounding data from these systems is a result of processing information from several data sources. Among them, positional data from Global Positioning System (GPS), ...
The world’s tides are a result of the combined forces of celestial forces and centrifugal force e... more The world’s tides are a result of the combined forces of celestial forces and centrifugal force exerted by the Earth‑Moon and the Sun acting on the water body, earth tides and the atmospheric tides. Harmonic analysis is the most popular and widely accepted method used for the processing and expression of tidal behavior as well as its characteristics. Despite its strengths, harmonic analysis has a few drawbacks when short data are involved for long term‑prediction. However, to enhance the accuracy of the popular methodology of harmonic analysis (HA), this study presents a wavelet‑based harmonic model for tidal analysis and prediction. Six months of water level heights at four tide gauge stations in Sabah and Sarawak of Malaysia were employed. The results obtained agrees with the original data when a comparison was made. The root mean square error (RMSE) and Pearson correlation coefficient (r) are the statistical index tools applied to test the functioning of the model. The residual e...
International Journal of Built Environment and Sustainability, 2021
Precise and accurate bathymetric measurements are conventionally acquired by means of ship-based ... more Precise and accurate bathymetric measurements are conventionally acquired by means of ship-based acoustic equipment. Nevertheless, recent multispectral satellite imagery has been utilised as a substitute source to map the seabed topography which indicates new revolution in hydrographic surveying. This study assesses the satellite bathymetric depth’s accuracy based on the vertical uncertainty as stated in the Standards for Hydrographic Surveys issued by the International Hydrographic Organization. Two empirical algorithms, namely, Dierssen’s and Stumpf’s approaches have been adopted to model the seafloor topography over the coastal and shallow water at Tanjung Kupang, Malaysia. The outcomes demonstrate a decent correlation between the derived water depths and the sounding values acquired from a ship-based acoustic survey. For instance, a total of 1,215 out of the 1,367 generated water depths by Stumpf’s model have hit the minimum standard of survey in S-44. Similarly, out of the 1,36...
One of the most impressive hydrographic technique developed over the past few decade is multibeam... more One of the most impressive hydrographic technique developed over the past few decade is multibeam sonar systems. Sounding data from these systems is a result of processing information from several data sources. Among them, positional data from Global Positioning System (GPS), ...
The world’s tides are a result of the combined forces of celestial forces and centrifugal force e... more The world’s tides are a result of the combined forces of celestial forces and centrifugal force exerted by the Earth‑Moon and the Sun acting on the water body, earth tides and the atmospheric tides. Harmonic analysis is the most popular and widely accepted method used for the processing and expression of tidal behavior as well as its characteristics. Despite its strengths, harmonic analysis has a few drawbacks when short data are involved for long term‑prediction. However, to enhance the accuracy of the popular methodology of harmonic analysis (HA), this study presents a wavelet‑based harmonic model for tidal analysis and prediction. Six months of water level heights at four tide gauge stations in Sabah and Sarawak of Malaysia were employed. The results obtained agrees with the original data when a comparison was made. The root mean square error (RMSE) and Pearson correlation coefficient (r) are the statistical index tools applied to test the functioning of the model. The residual e...
International Journal of Built Environment and Sustainability, 2021
Precise and accurate bathymetric measurements are conventionally acquired by means of ship-based ... more Precise and accurate bathymetric measurements are conventionally acquired by means of ship-based acoustic equipment. Nevertheless, recent multispectral satellite imagery has been utilised as a substitute source to map the seabed topography which indicates new revolution in hydrographic surveying. This study assesses the satellite bathymetric depth’s accuracy based on the vertical uncertainty as stated in the Standards for Hydrographic Surveys issued by the International Hydrographic Organization. Two empirical algorithms, namely, Dierssen’s and Stumpf’s approaches have been adopted to model the seafloor topography over the coastal and shallow water at Tanjung Kupang, Malaysia. The outcomes demonstrate a decent correlation between the derived water depths and the sounding values acquired from a ship-based acoustic survey. For instance, a total of 1,215 out of the 1,367 generated water depths by Stumpf’s model have hit the minimum standard of survey in S-44. Similarly, out of the 1,36...
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Papers by Ts. Dr. Kelvin Tang