• Journal of Wetlands Research
• /
• v.23 no.2
• /
• pp.107-115
• /
• 2021

In order to analyze wave propagation, tidal current, and sediment transport in the vicinity of the Gaeya open channel, it was classified into before(CASE1W) and after(CASE2W) installation of various artificial structures, and the calculation results for CASE1W and CASE2W were compared. For wave propagation, the results of incident and reflected waves were derived using the SWAN numerical model, and the tidal current velocity results were derived using the FLOW2DH numerical model for tidal current. The results of the SWAN numerical model and the FLOW2DH numerical model became the input conditions for the SEDTRAN numerical model that predicts sediment transport, and the maximum bed shear stress and suspended sediment concentration distribution near the Gaeya open channel were calculated through the SEDTRAN numerical model. As a result of the calculation of the SWAN numerical model, the wave height of CASE2W was increased by 40~50 % compared to CASE1W because the incident wave was diffracted and superimposed and the reflected wave was generated by about 7 km long northen jetty. As a result of the calculation of the FLOW2DH numerical model, According to the northen breakwater, the northen jetty and Geumrando, CASE2W was calculated 10~30 % faster than CASE1W in the tidal current of the Gaeya open channel. As a result of the calculation of the SEDTRAN numerical model, the section where the maximum bed shear stress is 1.0 N/m² or more and the suspended concentration is 80mg/L or more was widely distributed in the Gaeya open channel from the marine environment by the complex wave field(incident wave, reflected wave and tidal wave) and the installation of various artificial structures. it is believed that a sedimentation phenomenon occurred in the Gaeya open channel.

• Proceedings of KOSOMES biannual meeting
• /
• 2017.04a
• /
• pp.264-264
• /
• 2017

• Journal of Navigation and Port Research
• /
• v.29 no.3 s.99
• /
• pp.257-262
• /
• 2005

Environmental problems and safety problems in coastal area is one of the most important factors for designing coastal structures and maintaining facilities in coastal zone. And thus study on Wave transformation around coastal area is very important to develope a new port or on industrial area. Delft 3D-WAVE is applied to Ulsan new port area and the culculated results are analysed and compared with measured data Delft 3D-wave module is based on SWAN model which considers wave shoaling and refraction for irregular wave. This module also covers wind effect, bottom friction. white-capping and wave breaking effect. The results of this study show a good agreement with measured data and thus Delft 3D-WAVE module can be applied to simulate irregular wave transformation in coastal area.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.15 no.2
• /
• pp.62-67
• /
• 2010

Swells occurred on the coast of the East Sea on February 24, 2008 caused a loss of three lives and also damaged several west coasts of Japan. The recent increase of swell intensity with number of accidents demands more accurate forecasting of swells in terms of time and location. The swells occurred in February 2008 are hindcasted using SWAN model to examine the accuracy of the model for future forecasting. The model results are compared with ReWW3 data as well as measurement wave data and specially, wave spectrum is analysed by comparing with observed spectrum at two wave stations located in the east coast of Korea. The SWAN model shows similar results with observation data in terms of significant wave heights and swell arrival time but the shapes of wave spectrum are different between model and in-situ measurement data. For further improvement of swell forecasting, more comparison and analysis with observed wave spectrum is necessary and wave directional spectrum data are required to study on the characteristics of swells in the East Sea.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.26 no.7
• /
• pp.881-891
• /
• 2020

In recent years, large-scale development of coastal areas has caused the loss of many lives and extensive property damage in coastal areas, due to wave overtopping caused by high-wave invasion and strong typhoons. However, coastal inundation studies considering the characteristics of domestic coastal areas are insufficient. This study is a methodology study that aimed to reproduce inundation of surge and wave complex elements by applying the ADCSWAN (ADCIRC+SWAN) and FLOW-3D models. In this study, the boundary data (sea level, wave) of the FLOW-3D model was extracted using the ADCSWAN (ADCIRC+SWAN) model and applied as the input value of the FLOW-3D model and a reproduction was created of the Flooding due to surge and overtopping in Busan Marine City when the typhoon Chaba passed. In addition, the existing overtopping empirical equation and the overtopping calculated by the FLOW-3D model were compared, and for coastal inundation, a qualitative verification was performed using the Inundation Trace Map of Land and Geospatial Informatrix Corporation, and the effectiveness of this study was reviewed.

• Journal of Ocean Engineering and Technology
• /
• v.35 no.4
• /
• pp.273-286
• /
• 2021

In recent years, as human casualties and property damage caused by hazardous waves have increased in the East Sea, precise wave prediction skills have become necessary. In this study, the Simulating WAves Nearshore (SWAN) third-generation numerical wave model was calibrated and optimized to enhance the accuracy of winter storm wave prediction in the East Sea. We used Source Term 6 (ST6) and physical observations from a large-scale experiment conducted in Australia and compared its results to Komen's formula, a default in SWAN. As input wind data, we used Korean Meteorological Agency's (KMA's) operational meteorological model called Regional Data Assimilation and Prediction System (RDAPS), the European Centre for Medium Range Weather Forecasts' newest 5th generation re-analysis data (ERA5), and Japanese Meteorological Agency's (JMA's) meso-scale forecasting data. We analyzed the accuracy of each model's results by comparing them to observation data. For quantitative analysis and assessment, the observed wave data for 6 locations from KMA and Korea Hydrographic and Oceanographic Agency (KHOA) were used, and statistical analysis was conducted to assess model accuracy. As a result, ST6 models had a smaller root mean square error and higher correlation coefficient than the default model in significant wave height prediction. However, for peak wave period simulation, the results were incoherent among each model and location. In simulations with different wind data, the simulation using ERA5 for input wind datashowed the most accurate results overall but underestimated the wave height in predicting high wave events compared to the simulation using RDAPS and JMA meso-scale model. In addition, it showed that the spatial resolution of wind plays a more significant role in predicting high wave events. Nevertheless, the numerical model optimized in this study highlighted some limitations in predicting high waves that rise rapidly in time caused by meteorological events. This suggests that further research is necessary to enhance the accuracy of wave prediction in various climate conditions, such as extreme weather.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.31 no.2
• /
• pp.135-142
• /
• 2011

This experiment was carried out to compare the growth characteristics and forage productivity between Italian ryegrass (Lolium multiflorum Lam.) and Oats (Avena sativa L.) sown in early spring on trial field of Grassland and Forages Division, National Institute of Animal Science, RDA, Cheonan and Jeollanam-do Agricultural Research and Extension Services, Naju in 2007 and 2008. Varieties used were Swan and Foothill in early- and late-maturing Oats, and Kospeed and Hwasan 101 in early- and late-maturing Italian ryegrass, respectively. In early-maturing variety, heading date of Swan was 14 May that was earlier one day than that of Kospeed. Plant length of Swan was 92cm that was longer 4cm than that of Kospeed. Average dry matter (DM) yield of 3 trial regions was not significantly different between Kospeed (6,809 kg/ha) and Swan (6,756 kg/ha) but DM yield of Italian ryegrass Hwasan 101 was less 35% than that of Swan. Average total digestible nutrient (TDN) yield of 3 trial regions was not significantly different between Kospeed (4,240 kg/ha) and Swan (4,162 kg/ha). In paddy cultivation of Naju, TDN yield of Kospeed was 4,154 kg/ha that was more 45% than that of Swan. Forage feed value was similar Kospeed to Swan in early maturing variety. Considering TDN yield and feed value of forage, early-maturing variety of Italian ryegrass was effective for spring-sown cultivation and suitable for forage production on paddy in southland of Korea.

• Korean Journal of Veterinary Research
• /
• v.57 no.4
• /
• pp.257-260
• /
• 2017

Two Whooper swan (Cygnus cygnus) died after suffering from pododermatitis, lethargy, and ataxia; necropsy was performed. Grossly, the liver was swollen and firm. The kidney and spleen were also enlarged and a pale tan color. On histopathologic examination with Congo red staining, amyloidosis was noted in liver, spleen, and kidney. In addition, marked osseous metaplasia was present in the liver. Based on these results, systemic amyloidosis involving liver, spleen, and kidney with osseous metaplasia in the liver was diagnosed. Study results indicate that an inflammatory reaction associated with pododermatitis had a role in the amyloidosis in this particular case.

• The Journal of the Korea Contents Association
• /
• v.22 no.9
• /
• pp.510-519
• /
• 2022

This study aims to examine how delusions and hallucinations are expressed as representative symptoms of schizophrenia in the two films and . We look at how the two films show the appearance and overall image of the schizophrenic patient, the emotional expression of the schizophrenic patient, and how family and colleagues express the perceptions of the schizophrenic patient's symptoms. Finally, we will examine the perception of treatment measures for schizophrenia. Comprehensively, through this process, the schizophrenia symptoms expressed in the two films will have some effect on social perception of schizophrenia and the social implications of therapeutic intervention for schizophrenia recovery.

• Korean Journal of Environment and Ecology
• /
• v.34 no.3
• /
• pp.191-197
• /
• 2020

The purpose of this was to examine the differences of large whopper swan (Cygnus cygnus) in wintering habitat preference among bridge sections of the lower Nakdong River of the Nakdong River Estuary, the largest whopper swan's wintering habitat in Korea. This species is designated and protected as Natural Monument in Korea. The survey was conducted in six time-series during the 2018~2019 wintering season, and it found up to 500 whopper swans were wintering in the lower Nakdong River. For the survey, a seven sections were set up based on the bridges across the river. Whopper swans were rarely observed in five narrow sections where the distance between bridges was less than 2 km. The stable population of the whopper swan was observed only in two broader sections where the distance between bridges was is over 4 km. As these sections were relatively little affected by artificial interference, the distance from the mouth of the Nakdong River was not a factor. Securing a stable space is considered as one of the most important factors for wintering of whopper swans, which are an endangered species. The survey results indicate that the distance between bridges should be at least 4 km to secure the whopper swan's stable habitat. These results are expected to be a reference to the development or restoration of the river ecosystems, especially bridge construction.