• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.6
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• pp.511-520
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• 2007

WAM(WAve Model), deep water wave model has been extended to the region of shallow water, incorporating wave breaking, and triad wave interaction. To verify the model, numerical simulation of waves in Youngil bay, Pohang is performed and the simulated results show good agreements with measured wave data sets, one station at the mouth of bay and two stations inside the bay. As waves propagate toward the shore, wave height gradually diminishes by bottom friction and wave breaking, and wave direction, initially NE changes normal to the shore due to depth refraction.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.164-165
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• 2003

본 연구는 영일만 만내 수괴의 거동에 영향을 미칠 것으로 판단되는 가용 강우량, 증발량, 바람 등 기상조건의 영향을 검토ㆍ분석하고, 그림 1의 영일만 정선해양관측의 수온ㆍ염분 자료와 연안정지 수온관측자료를 수집ㆍ분석하여 영일만 해역에서의 동해 고유수와 만내 연안수와의 혼합과정을 규명하고자하였다. 이를 통해 영일만수괴의 만내 연안수와 동해 고유수와의 상호관련성과 만내 해수의 수평ㆍ연직순환류 발생 메카니즘에 대해서 고찰하고자 하였다. (중략)

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.231-231
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• 2022

하구에서의 흐름은 하천의 담수와 바다에서부터 유입되는 염수, 조석, 파랑 등으로 인해 복잡한 흐름구조와 혼합 양상을 보인다. 특히 만 내에 하천이 있을 경우 만의 해류특성은 하구에서의 혼합과 이송에 지배적인 영향을 미치며, 하천에서부터 방류되는 입자들은 만의 해류특성 따라 만에서의 체류시간과 이송이 결정된다. 잔차류 특성에 의한 순 물질 플럭스의 방향과 조석비대칭에 따른 하구에서의 퇴적 형태들이 결정되며, 이로 인해 하구에서의 퇴적물 퇴적 및 물질의 집적 위치, 하구 인근과 만에서의 환경변화에 영향을 줄 수 있다. 따라서 만 내에서의 혼합과 입자의 이송확산, 하천 담수의 영향역 등과 같은 만과 하천의 흐름 특성을 이해하는 것은 연안 및 하구의 환경 및 관리에 중요하다. 본 연구에서는 영일만과 형산강을 대상으로 계절변화에 따른 영일만 내 흐름과 형산강 하구에서의 퇴적양상에 대해 수치모의를 통해 수행하였다. 수치모델로는 천수방정식으로 준 3차원 유동해석을 하는 Delft-3D Flow와 파랑모형인 SWAN 모델을 결합하여 형산강하구와 영일만의 유동을 해석하였다. 상류개방경계는 형산강하구 9 km, 하류개방경계는 영일만 외해 50 km로 설정하였고, 경계조건은 대상지역의 관측소 자료와 전지구 모형자료를 결합하여 구성하였다. 또한, 라그랑쥬 입자추적모델을 통해 형산강 상류에서 유입한 입자들의 영일만 내 체류시간과 집적 위치를 평가하였다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.21 no.1
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• pp.62-66
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• 1985

The periodic variations of the surface water temperature and the relationships between the surface water and air temperature are found in Youngil bay as follows: It is considered that the average surface water temperature is the lowest in February and the highest in August in the Youngil bay (Pohang bay and Janggi cape) from January, 1962 to December, 1981. It is only in October and November that the average surface water temperature was higher in pohang bay than in the Janggi cape from January, 1962 to December, 1981. Since the periodic secular variation in the vincity of Youngil bay and the variation of the Tsushima Current seem to have similar tendencies, we may conclude that the changes of the surface water temperature in Youngil bay are primarily influenced by the Taushima Current. The average temperature of surface water is 14.5$^{\circ}C$ in Pohang bay and 15.$0^{\circ}C$ in Janggi cape in the secular variation.

• 한국해양학회지
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• v.9 no.2
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• pp.59-64
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• 1974

Relative light intensity was observed with underwater illuminometer (Cs Photoelectric cell, glass window) at the mouth of Yeong-il Bay, and relative vertical clearness and extinction coefficient were calculated from the relative light intensity data. Relationship between extinction coefficient and transparency in this region is also shown.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.67-67
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• 2021

하구에서의 흐름은 하천의 담수와 바다에서부터 유입되는 염수, 조석, 파랑 등으로 인해 복잡한 흐름구조와 혼합 양상을 보인다. 특히 만 내에 하천이 있을 경우 만의 해류특성은 하구에서의 혼합과 이송에 지배적인 영향을 미치며, 하천에서부터 방류되는 입자들은 만의 해류특성 따라 만에서의 체류시간과 이송이 결정된다. 잔차류 특성에 의한 순 물질 플럭스의 방향과 조석비대칭에 따른 하구에서의 퇴적 형태들이 결정되며, 이로 인해 하구에서의 퇴적물 퇴적 및 물질의 집적 위치, 하구 인근과 만에서의 환경변화에 영향을 줄 수 있다. 따라서 만 내에서의 혼합과 입자의 이송확산, 하천 담수의 영향역 등과 같은 만과 하천의 흐름 특성을 이해하는 것은 연안 및 하구의 환경 및 관리에 중요하다. 본 연구에서는 영일만과 형산강을 대상으로 계절변화에 따른 영일만 내 흐름과 형산강 하구에서의 퇴적양상에 대해 수치모의를 통해 수행하였다. 수치모델로는 천수방정식으로 준 3차원 유동해석을 하는 Delft-3D Flow와 파랑모형인 SWAN 모델을 결합하여 형산강 하구와 영일만의 유동을 해석하였다. 상류개방경계는 형산강하구 9 km, 하류개방경계는 영일만 외해 50 km로 설정하였고, 경계조건은 대상지역의 관측소 자료와 전지구 모형자료를 결합하여 구성하였다. 또한, 라그랑쥬 입자추적모델을 통해 형산강 상류에서 유입한 입자들의 영일만 내 체류 시간과 집적 위치를 평가하였다.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.3
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• pp.140-147
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• 2005

We investigated the interactions between coastal waters of the Yeongil Bay, Korea, and oceanic waters of the Eastern Sea, as wet 1 as the development mechanism of vertical circulation currents in the bay. The oceanic waters of the bay have an average water temperature of $12.2{\sim}18.4^{\circ}C$ and salinity of $33.32{\sim}34.43$ PSU. Results of spectral analysis have shown that the period of revolution between oceanic and coastal waters is about 0.84-0.91 years in the surface waters and 1.84 years in the bottom layer. The wind direction in the bay shifts between SW and NE, with the main wind direction being SW during the winter period, and water mass movement is influenced by such seasonal variations in wind direction. Vertical circulation currents in the bay are structured by two phenomena: the surface riverine outflow layer from the Hyeong-san River into the open sea and the bottom oceanic inflow layer with high-temperature and salinity into the bay. These phenomena start the spring when the water mass is stable and become stronger in the summer when the surface cold water develops over a 10-day period. Consequently, tidal currents have little influence in the bay; rather, these vertical and horizontal circulation currents play an important role in the transport of the pollutant load from the inner bay to the open sea.

• The Korean Journal of Petroleum Geology
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• v.1 no.1 s.1
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• pp.53-62
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• 1993

The geologic structure of the Yongil Bay was studied in detail based on high resolution seismic profiles. The seafloor trends NE to SW with a deeper part off the Kuryong Peninsula. The seafloor is rather smooth due to the Quaternary fluvial deposits in the lower part and muddy sediments in the upper part. The seafloor off Umockri is very irregular due to erosion where Tertiary sedimentary rocks crop out. The underlying basement rocks were strongly deformed with faults and folds. High-angled reverse faults mostly trend N-S and NNW-SSE and are indicative of westward thrusting. Normal faults in NW-SE and WNW-ESE directions occur locally. Large folding structures trend NE-SW nearshore area of Umockri. The geologic structure suggests that the bay was subject to compressional stress regimes trending E-W and/or NW-SE prior to the early Late Miocene.

• Journal of the Korean Society for Marine Environment & Energy
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• v.6 no.3
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• pp.63-71
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• 2003

This study investigated about the seasonal variation of pollutant loads flowing into the Yeong-il bay from constructing Tank model which is the simulation model to evaluate the daily river discharge and pollutant load in the Hyeong-san river watershed. The estimated annual average river discharge of Hyeong-san river flowing into Yeong-il bay is about 878.34×10/sup 6/㎥/year which is about 73% of annual average of total precipitation in Hyeong-san river watershed. The annual average of pollutant load flowing into Yeong-il bay was estimated each 15.11 ton-COD/year, 23.24 ton-SS/year, 10.65 ton-TN/year, and 0.54 ton-Tp/year. For the seasonal variation of pollutant loads, it was tended as increasing of river discharge as increasing of inflow pollutant loads at June and July of summer and October of autumn. The main source of pollutant loads was found to be the Pohang city and Pohang industrial complex which are located near the mouth of Hyeong-san river. Therefore, for effective water quality management of Yeong-il bay, the counterplan to reduce pollutant loads from the main source of pollutant loads is required.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.3
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• pp.197-201
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• 1983

Underwater ambient noise level was measured at two points near the Youngil Bay. The environmental characteristics depend upon oceanographic conditions of sound propagation ana its implication on the source of ambient noise. Some noise sources were estimated, and the effect of the oceanographic conditions on the noise level variation had been considered. The results were as follows : 1) At the nearshore station of Youngil Bay, the ambient noise level in the near bottom(45m) was lower than that of the near surface(10m) by 15dB. This difference was due to spherical spreading from the upper to the lower layer. 2) At the open sea station which is located outside of the thermal front existing near the Youngil Bay, the ambient noise level of the upper layer(20m) was higher than that of the lower layer (100m) by $8{\sim}12dB$ below 50Hz and $15{\sim}23dB$ above 50Hz. 3) Above 60Hz the ambient noise level at the nearshore station was higher than that of the open sea station, while below 60Hz, the result was reverse. It appears that a boundary layer existed between the two stations.