• Journal of Korean Society of Coastal and Ocean Engineers
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• v.16 no.4
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• pp.258-267
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• 2004

Coastal and harbor structures, which are constructed for the beach protection and coastal zone development, often cause the severe beach erosion problem resulted from changes of longshore sediment transport. In this study, we present a new methodology to estimate the longshore sediment transport rates using the measured data of beach profiles or shorelines. The methods is applied for the prediction of longshore sediment transport rates along Kailua beach, Hawaii and shorelines in the vicinity of Anmok Harbor, Korea.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.1
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• pp.29-41
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• 1996

The two-stage numerical model was used to study the relation between three-dimensional local wind model, advection/diffusion model of random walk method and second moment method on Pusan coastal area. The first stage is three dimensional time-dependent local wind model which gives the wind field and vertical dirrusion coefficient. The second stage is advection/diffusion model which uses the results of the first stage as input data. First, wind fields on Pusan coastal area for none synoptic scale wind showed typical land and sea breeze circulation, and convergence zone occured at 1200LST in northern of domain, in succession, moved northward of domain. Emissions from Sinpyeong industrial district were trasnported toward the inland by sea breeze during daytime, and reached the end part of domain about 1800LST. During nighttime, emissions return to sea by land breeze and vertical diffusion also contributes to upward transport. In order to use this model for forecast of air pollution concentration on the Pusan coastal area, it is necessary that computed value must be compared with measured value and wind fields model must also be dealt in detail.

• Journal of Environmental Science International
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• v.6 no.4
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• pp.335-350
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• 1997

Numerical simulations of photochemical air pollution (CBM: Carbon-Bond Mechanisms under a theoretical three-dimensional local wind system are carried to clarify the fundamental characteristics of the effects of local wind on photochemical air pollution. According to the AWS data of Pusan coastal area and KMA, the surface wind of Pusan during summertime showed a very remarkable land and sea breeze circulation. The ozone concentration distribution using local wind model showed that high ozone concentration zone near coastal area moved toward inland In the afternoon. This change implies a sea breeze Increases the ozone concentration, but a land breeze decreases it in Pusan coastal area.

• Journal of the Korean Institute of Navigation
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• v.16 no.1
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• pp.37-64
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• 1992

A study on the changes of the oceanographical environment caused by Mokpo coastal zone development was carried out. Special emphasis was placed on the clarification of the water level changes and coastal current structure and influence of the environmental factors on the coastal area. In order to understand the structure oceangraphical environemnt, such as water temperature, salinity, suspended solids, pH, dissolved oxygen, chemical oxygen demand, biochemical oxygen demand, distribution of bottom sediment, tide and current were measured. To investigated the structure of tide and current for the future development, a numerical analysis was carried out. In certain zones, it was found to be flooding problems near the lowlying commercial area.

• The Journal of the Korea Contents Association
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• v.18 no.1
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• pp.154-163
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• 2018

Not only South Korea but also Global world show that the frequency and damages of large-scale natural disaster due to the rise of heavy rain event and typhoon or hurricane intensity are increasing. Natural disasters such as typhoon, flood, heavy rain, strong wind, wind wave, tidal wave, tide, heavy snow, drought, earthquake, yellow dust and so on, are difficult to estimate the scale of damage and spot. Also, there are many difficulties to take action because natural disasters don't appear precursor phenomena However, if scale of damage can be estimated, damages would be mitigated through the initial damage action. In the present study, therefore, wind wave damage estimation functions for the western coastal zone are developed based on annual disaster reports which were published by the Ministry of Public Safety and Security. The wind wave damage estimation functions were distinguished by regional groups and facilities and NRMSE (Normalized Root Mean Square Error) was analyzed from 1.94% to 26.07%. The damage could be mitigated if scale of damage can be estimated through developed functions and the proper response is taken.

• Journal of Coastal Disaster Prevention
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• v.4 no.spc
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• pp.245-253
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• 2017

In this study, surface currents measured by small lagrangian GPS drifters (Aquadrifter) in Anmok coastal waters were analysed to account for the variability of nearshore surface current and wave-induced current to understand sediment transport mechanism near the crescentic bars in the surf-zone and near Kangneung breakwater and submerged breakwater in Anmok. The 8 times lagrangian drifter experiments were conducted mostly during in 2nd, 3rd, 4th intensive measurements in winter, summer, and spring seasons with long-term wave observation at the station W1. The analysed surface currents near the breakwaters in Anmok show that wave-induced currents at the middle of the submerged breakwater were separated and flowed toward the shoreline but offshore currents were dominant through the channels between the breakwaters. The longshore currents near the shoreline were flowed to the northwest (southeast) depending on the incoming waves from ENE (NNE). The surface nearshore offshore currents were generated mostly by waves and winds in case of high and low wave energy environments. Using the small-size lagrangian surface drifter experiments, we successfully measured longshore and offshore wave-induced currents in the surf-zone and near submerged breakwater close to Kangneung breakwater. The drifter experiment results show the availability of direct observation of nearshore surface currents to understand the mechanism of sediment transport analysing observed wave-induced current and ebb-current in the surf-zone generated by incoming waves and local winds.

• Proceedings of KOSOMES biannual meeting
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• 2018.06a
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• pp.142-142
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• 2018

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1992.08a
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• pp.106-113
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• 1992

쇄파대에서 파고의 감쇠 및 내부유속장에 대한 이해는 표사문제 및 해안구조물의 설계 등에 있어서 중요하다(Nadaoka and Kondoh, 1982). 특히 해빈변형의 예측문제에 있어서 가장 중요한 문제의 하나는 쇄파대 내ㆍ외에서 저면마찰력과 표사량을 정도 높게 계산하는 것이다.(중략)

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1991.07a
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• pp.40-45
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• 1991

항만 건설, 매립, 임해 발전소의 걸선, 호안 축조 및 신공간 개발 등 연안역 개발시 설계 환경요소인 파랑을 정확히 예측함으로써 이러한 사업을 경제적으로 수행 할 수 있다. 특히 이들 구조물은 대부분 쇄파대내에 위치하므로 쇄파후의 파랑변형 및 Runup 등을 파악하여야 한다. 본 연구에서는 조파수조를 이용하여 쇄파후의 파고 및 Runup 등을 관측하여 경험식 및 해석해와 비교하였다.(중략)

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.1
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• pp.45-52
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• 1998

The transport of suspended matter was interpreted in the coastal zone off Taean Peninsula during the summer (June) in 1996. Coastal waters were homogenous in water temperature and salinity, whereas offshore waters were characterzed by the strong thermocline. Mixing between coastal and offshore waters are negligeable, largely lessened, due to the existence of strong tidal front between the two water masses. In the offshore area, less saline coastal waters from the Kyunggi Bay are considered to be transported southward along the mid-depth layer of thermocline. Concentration of suspended matters was higher than 5 mg/l in the northern coastal area near the Kyunggi Bay, but generally less than 2 mg/l in the offshore area. Less saline waters along the mid-depth layer in the offshore area sustain maximum turbidities throughout the water column. Therefore suspended matters supplied from the coastal area of Kyunggi Bay are considered to be transported southward by the advective movement of less saline coastal waters. Mean particle size of the suspended matters shows 2~9 ${\mu}m$. Coarse grains (mean size larger than 7 ${\mu}m$) are predominant in the less saline coastal waters extending to the offshore mid-depth waters. Such size distributions of suspended matters together with the characteristics of water masses are considered to be an indicator for the southward movement of suspended matters derived from Kyunggi Bay.