• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.2941-2951
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• 2018

The purpose of this paper is to analyse the effect of ocean weather factors on shipments of swimming crab. We use the data of data portal and ocean weather factors (mean wind velocity, mean atmospheric pressure, mean relative humidity, mean air temperature, mean water temperature, mean maximum wave height, mean significant wave height, maximum significant wave height, maximum wave height, mean wave period, maximum wave period). We did statistical analysis using Poisson regression analysis and negative binomial regression analysis. As the result of study, important factors influential in the shipments of swimming crab turn out to be mean wind velocity, mean atmospheric pressure, mean relative humidity, mean water temperature, maximum wave height, mean wave period and maximum wave period. the shipments of swimming crab increases as mean wind velocity, mean atmospheric pressure, mean relative humidity, mean water temperature increases or mean wave period increase. However, as maximum wave height, maximum wave period decreases, the shipment of swimming crab increases.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.05a
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• pp.216-221
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• 2001

In this paper, statistical properties of waves in the sea area of Pohang, Korea are examined absed on 1998-1999's wave data from directional wave buoy which is located Pohang(Janggigog). Wave data aquisition rate, monthly maximium, minimum and mean wave heights, frequency of wave direction are summarized. Wave height and period scatter diagrams and n-year return period wave heights are estimated. Wave periods of maximum wave heights are also estimated.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.10a
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• pp.108-116
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• 2001

In this paper, statistical properties of waves in the sea area of Mara-do, Korea are examined based on 1998-1999's wave data from a directional wave buoy which is located in Mara-do. Wave data aquisition rate, monthly maximium, minimum and mean wave heights, frequency of wave direction are summarized. Wave height and period scatter diagrams and n-year return period wave heights are estimated. Wave periods of maximum wave heights are also estimated.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.309-316
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• 2003

In this paper, The statistical properties of ocean waves in the sea area of Hong-do, Korea are examined based on 1998-2002's wave data from a directional wave buoy. Wave data aquisition rate, mean wave heights, frequency of wave direction are summarized. Wave height and period scatter diagrams and n-years return period wave heights are estimated. Wave periods of maximum wave heights are also estimated. Large amplitude wave characteristics during the typhoon Prapiroon in 2000, Rusa in 2002 are also examined.

• Journal of Navigation and Port Research
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• v.36 no.9
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• pp.729-735
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• 2012

The primary wave energy conversion by a three-dimensional bottom-mounted oscillating water column (OWC) wave power device in regular waves has been studied. The linear potential boundary value problem has been solved following the boundary matching method. The optimum shape parameters such as the chamber length and the depth of the front skirt of the OWC chamber obtained through two-dimensional numerical tests in the frequency domain have been applied in the design of the present OWC chamber. Time-mean wave power converted by the OWC device and the time-mean second-order wave forces on the OWC chamber structure have been presented for different wave incidence angles in the frequency-domain. It has been shown that the peak period of $P_m$ for the optimum damping parameter coincides with the peak period of the time.mean wave drift force when ${\gamma}=0$.

• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.3
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• pp.137-145
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• 2004

Long-term wave distribution at Jeju sea is investigated by a numerical simulation based on the thirdgeneration wave model SWAN (Simulating WAves Nearshore). The Jeju sea which retains relatively high wave energy density among Korean coastal regions is considered to be a suitable site for wave power generation and the efficiency of wave power generation is closely related to local wave characteristics. The monthly mean of a large-scale long-term wave data from 1979 to 2002, which is provided by Korea Ocean Research & Development Institute. is used as the boundary condition of SWAN model simulation with 1km grid. An analysis of wave distribution concentrates on the seasonal variation and spatial distribution of significant wave heights, mean wave directions and mean wave periods. Significant wave heights are higher in winter and summer and the west sea of Jeju appears relatively higher than east's. The highest significant wave height occurs at the northeast sea in winter and the second highest significant wave height appears at the southeast sea in summer, while the significant wave heights in spring and autumn are relatively low but homogeneous. The distribution of wave directions reveals that except the rear region influenced by wave refraction, the northwest wave direction is dominant in summer and the southeast in winter. Wave periods are longer in summer and winter and the west sea of Jeju appears relatively longer than east's. The longest wave period occurs at the west sea in winter, and in summer it appears relatively homogeneous with a little longer period at the south sea.

• Korean Journal of Remote Sensing
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• v.39 no.4
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• pp.441-458
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• 2023

Tropical cyclones frequently occur in the Southwest Pacific Ocean and are considered one of the driving forces for coastal alterations. Therefore, this study investigates the frequency and intensity of tropical cyclonesfrom 2000 to 2021 and their influence on the surface winds and wave conditions around the atoll nation Tuvalu. Cyclone best-track and ERA5 single-level reanalysis data are utilized to analyze the condition of the surface winds, significant wave heights, mean wave direction, and mean wave period. Additionally, the scatterometer-derived wind information was employed to compare wind conditions with the ERA5 data. On average, nine cyclones per year originated here, and the frequency increased to 11 cyclones during the last three years while the intensity decreased by 25 m/s (maximum sustained wind speed). Besides, a total of 14 cyclones were observed around Tuvalu during the period from 2015 to 2021, which showed an increase of 3 cyclones compared to the preceding period of 2001 to 2007. During cyclones, the significant wave height reached the highest 4.8 m near Tuvalu, and the waves propagated in the east-southeast direction during most of the cyclone events (52%). In addition, prolonged swells with a mean wave period of 7 to 11 seconds were generated in the vicinity of Tuvalu, for which coastal alteration can occur. After this preliminary analysis, it was found that the waves generated by cyclones have a crucial impact in altering the coastal area of Tuvalu. In the future, remotely sensed high-resolution satellite data with this wave information will be used to find out the degree of alterations that happened in the coastal area of Tuvalu before and after the cyclone events.

• Water for future
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• v.10 no.1
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• pp.101-117
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• 1977

The statatistical characteristics and spectra of sea waves at Mookho were analysed by several statistical methods. As the results, the following conclusions are obtained: 1. Values of surface elevation of sea wave are better fitted to Gram Charlier distribution than Gaussian distribution. This proves that sea waves have not only characters of irregularity but also non-linearity. 2. Distribution of maxima of surface elevation practically follows the distribution of Cartwright and Longuet-Higgins, also spectral width parameter is found to be increased with the increase of root mean square of surface elevation. 3. Sea wave may have spectrum of broad frequency band, however distributions of wave heights and periods follow the Rayleigh distribution which is derived from the assumption of narrow frequency band. 4. Ratios among mean wave heights from observed data show good agreements with theoretical values from Rayleigh distribution. 5. Spectral density and spectral width parameter increase with increase of wind velocity. And wave period at optimum band gas higher value than significant wave period by about 10 percent.

• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.1
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• pp.47-55
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• 2004

In this paper, The statistical properties of ocean waves in the sea area of Hong-do, Korea are examined based on 1998-2002's wave data from a directional wave buoy. Wave data aquisition rate, mean wave heights, frequency of wave direction are summarized. Wave height and period scatter diagrams and n-year return period wave heights are estimated. Wave periods of maximum wave heights are also estimated. Large amplitude wave characteristics during the typhoon Prapiroon in 2000, Rusa in 2002 are also examined.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.15 no.1
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• pp.11-20
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• 2003

In this paper we examine several methods tor calculating the reflection of irregular waves from a perforated-wall caisson breakwater using a regular wave model. The first method is to approximate the irregular waves as a regular wave whose height and period are the same as the root-mean-squared wave height and significant wave period, respectively, of the irregular waves. The second is to use the regular wave model, repeatedly, for each frequency component of the irregular wave spectrum. The wave period is determined according to the frequency of the component wave, and the root-mean-squared wave height is used for all the frequencies. The third method is the same as the second one except that the wave height corresponding to the energy of each component wave is used. Comparison with experimental data from previous authors shows the second method is the most adequate, giving reasonable agreement in both frequency-averaged reflection coefficients and reflected wave spectra.