• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.1
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• pp.63-78
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• 2009

This paper presents the development of dynamically combined Typhoon generated surge-tide-wave numerical model which is applicable to shallow water. The newly developed model is based on both POM (Princeton Ocean Model) for the surge and tide and WAM (WAve Model) for wind-generated waves, but is modified to be applicable to shallow water. In this paper which is the first paper of the two in a sequence, we verified the accuracy and numerical stability of the hydrodynamic part of the model which is responsible for the simulation of Typhoon generated surge and tide. In order to improve the accuracy and numerical stability of the combined model, we modified algorithms responsible for turbulent modeling as well as vertical velocity computation routine of POM. Verification of the model performance had been conducted by comparing numerical simulation results with analytic solutions as well as data obtained from field measurement. The modified POM is shown to be more accurate and numerically stable compare to the existing POM.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.18 no.3
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• pp.198-210
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• 2006

POM(Princeton Ocean Model) was utilized in this study because it took ${\sigma}-coordinate$ system which could predict the behavior of bottom water. The model has been increasingly applied to costal area although it was initially developed as the ocean flow model. The original POM did not correct computational errors in transformation of ${\sigma}-coordinate$ system. The trying to reduce conversional errors might improve accuracy of flow velocity in vicinities of bottom layer. Therefore, in this study it was proposed to modify the original POM by using error correction method suggested by $Sl{\Phi}rdal$(1997). The modified POM was applied to Young-rang Lake, one of the typical brackish lakes in Korea. It was found that the behavior of bottom water could be well predicted. Thus, it seems that the modified POM can be used as a useful tool to clarify the mechanism of formation and behavior of bottom water including oxygen-deficient water mass.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.12 no.2
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• pp.70-80
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• 2000

Princeton Ocean Model (POM) is modified to construct a three-dimensional, semi-implicit hydro¬dynamic model with a wetting-and-drying scheme. The model employs semi-implicit treatment of the barotropic pressure gradient terms and the vertical mixing terms in the momentum equations, and the velocity divergence term in the vertically-integrated continuity equation. Such treatment removes the external mode and thus the mode splitting scheme in POM, allowing the semi-implicit model to use a larger time step. Applied to hypothetical systems, both the semi-implicit model and POM give nearly the same results. The semi-implicit model, however, runs approximately 4.4 times faster than POM showing its improved computational efficiency. Applied to a hypothetical system with intertidal flats, POM employing the mode splitting scheme produces noises at the intertidal flats, that propagate into the main channel resulting in unstable current velocities. Despite its larger time step, the semi-implicit model gives stable current velocities both at the intertidal flats and main channel. The semi-implicit model when applied to Kyeonggi Bay gives a good reproduction of the observed tides and tidal currents throughout the modeling domain, demonstrating its prototype applicability.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.1
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• pp.79-90
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• 2009

This paper presents the development of dynamically combined Typhoon generated surge-tide-wave numerical model which is applicable from deep to shallow water. The dynamically coupled model consists of hydrodynamic module and wind wave module. The hydrodynamic module is modified from POM and wind wave module is modified from WAM to be applicable from deep to shallow water. Hydrodynamic module computes tidal currents, sea surface elevations and storm surges and provide these information to wind wave module. Wind wave mudule computes wind waves and provides computed information such as radiation stress, sea surface roughness and shear stress due to winds. The newly developed model was applied to compute the surge, tide and wave fields by typhoon Maemi. Verification of model performance was made by comparison of measured waves and tide data with simulated results.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2002.03b
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• pp.61-68
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• 2002

GIS와 하천수질 모델링과의 연계에 관한 연구는 점점 많아지고 계속되고 있는 실정이다. 그러나 해양모델링과 GIS와 연계한 연구는 많지 않다. 이번 연구에서는 해양모델을 GIS와 연계하는 측면을 고려해 보았다. 해양모델 중에 해수유동에 관한 모델 POM(princeton Ocean Model)을 선정하여 해양모델의 구동을 위해 자료를 만드는 것과 결과물을 도시하는 데 있어서 GIS를 사용한다. 그래서 기존의 해양모델을 사용하는 측면에서의 편이성을 도모하고, 또한 해양모델의 구동을 위해 자료 만드는 측면에서 정확성을 높이게 한다.

• Atmosphere
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• v.21 no.3
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• pp.311-317
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• 2011

Aerosol optical properties from the radiation measurements by SKYNET PREDE skyradiometers, POM-01 and POM-02 were compared during the inter-calibration campaign at Seoul in February 2009. The monochromatic solar flux at the top of the atmosphere ($F_0$) gave a relative standard deviation (RSD) of 9-10% for both instruments. This comparatively high value of RSD was probably because $F_0$ was determined at short time intervals, in the morning and afternoon, using the measurements made in the polluted environment of Seoul. Although POM-02 was more effective in tracking the solar radiation, aerosol optical depths (AODs) from the two instruments were very similar after the cloud screening procedure. The squared correlation coefficients ($R^2$) of single scattering albedo (SSA) and real and imaginary refractive indices between the two instruments was around 0.5 but increased to 0.7-0.8 when only using AOD greater than 0.4. Nevertheless, mean values of the Angstrom exponent, SSA, and the imaginary refractive index of POM-02 were higher than those of POM-01.

• Journal of the Korean Society of Marine Environment & Safety
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• v.9 no.2
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• pp.53-57
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• 2003

Low salinity water appears by outflow of fresh water from the Yangtze River in southwestern sea of the Korean peninsula. The water volume discharged form the Yangtze River is not constant with year, according to the time series data recorded in the past, the maximum value of the discharged volume is two times as high asr minimum value. Therefore, the distribution of low salinity water over study area with different discharged fresh water volume is studied using numerical model, Princeton Ocean Model (POM). POM is three dimensional circulation model selecting a $\sigma$­coordinate. According to the result of numerical simulation by the Model, current velocity on the continental slope is faster than those in other regions, current which flows toward the central part of the Yellow Sea through western part of Jeju exists, and also, southward flow along the coastal region exists. the greater discharged volume from the Yangrze River is. the lower salinity water appears closer to Jeju.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2009.10a
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• pp.160-163
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• 2009

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.6
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• pp.373-383
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• 2020

In this study we established an operational storm-surge system for the northwestern pacific ocean, based on the NEMO (Nucleus for European Modeling of the Ocean). The system consists of the tide and the surge models. For more accurate storm surge prediction, it can be completed not only by applying more precise depth data, but also by optimal parameterization at the boundaries of the atmosphere and ocean. To this end, we conducted several sensitivity experiments related to the application of available bathymetry data, ocean bottom friction coefficient, and wind stress and air pressure on the ocean surface during August~September 2018 and the case of typhoon SOULIK. The results of comparison and verification are presented here, and they are compared with POM (Princeton Ocean Model) based Regional Tide Surge forecasting Model (RTSM). The results showed that the RTSM_NEMO model had a 29% and 20% decrease in Bias and RMSE respectively compared to the RTSM_POM model, and that the RTSM_NEMO model had a lower overall error than the RTSM_POM model for the case of typhoon SOULIK.

• Proceedings of KOSOMES biannual meeting
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• 2003.11a
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• pp.187-190
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• 2003

한반도 서남부해역은 하계 양자강의 방류에 의해 저염분 현상이 발생한다. 양자강 방류량은 해마다 일정하지 않으며, 과거 시계열자료에 의하면 최대값이 최소값보다 2배 이상이 됨을 알 수 있다. 다라서 양자강의 방류량을 달리하여 저염분포를 수치모델로 연구하고자 하였다. 수치모델은 POM(Princeton Ocean Model)을 사용하였다. POM은 연직적으로 $\sigma$-좌표계를 사용하는 3차원 순환모델이다. 모델 수행 후 연구해역내 대륙사면부에서 유속이 강하게 나타남을 알 수 있다. 또한 제주도 서쪽을 통해 북상하여 황해중앙부로 들어가는 흐름이 있으며, 대륙연안을 따라 남하하는 흐름이 있음을 알 수 있다 양자강 방류량을 부여한 수행한 모델의 결과를 보면 양자강 방류량이 많을수록 저염분역이 제주도에 가깝게 나타남을 랄 수 있다.