• 한국항만학회지
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• 제13권1호
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• pp.123-132
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• 1999

It is very important to quantitatively assess the movement of sea water and pollutant dispersion before or after constructing shore structures such as breakwater considering marine environment and long-term utilization of those structures. This assesment is possible through the use of simulation models designed to predict water movement and pollutant dispersion in a certain area. In this study the numerical computations were carried out to predict the sea water quality in the Ilgwang Harbor located at the east coast of Pusan. The flow patters were investigated before and after the development of Ilgwang Harbor. The computational models adopting ADI Method (Alternating Direction Implicit Method) were used here and were already verified from the previous studies. As a results of this study the tidal exchange in Ilgwang Harbor after development proved to be worse due to the increased semi-enclosed at the harbor limit. In order to improve the water quality of this area after development a new method was proposed to improve water quality in the semi-enclosed bay by creation and control of tidal residual currents. For this purpose the unsymmetric structures so called bottom roughness were introduced in this study. The simulation was carried out on the basis of the study by Komatsu et. al. and Gug and we made a conclusion that it is possible to generate a new tidal residual current and to increase the tidal exchange by application of bottom roughness arrangement.

• Ocean and Polar Research
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• 제25권3호
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• pp.257-267
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• 2003

Deep-sea bottom photographs acquired in the Clarion-Clipperton fracture zone of the northeast equatorial Pacific were analyzed to reveal the controlling processes for the spatial variation of manganese nodule. The results show that regional-scale occurrence variations of manganese nodule are mainly controlled by primary productivity of surface water, sedimentation rate, and water depth (or carbonate compensation depth). As a result, the diagenetic accretion on nodules increases toward southwest while hydrogenetic accretion increases toward northeast. Considering the northwestward movement of Pacific Plate, this regional-scale variation of manganese nodule occurrence seems to be affected by oceanic environment during the active growth period (Oligocene-Miocene) of Pacific Plate.

• Ocean and Polar Research
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• 제25권4호
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• pp.437-446
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• 2003

Field measurements of directional waves were carried out during the summer of 2002 at two coastal sites in water of finite depth. A couple of general purpose instruments were used employing acoustic Doppler technology. The aim of the study was to investigate the spatial behavior of the directional movement of waves as they come ashore. In total,74 tests were carried out during which sea states of low to moderate intensity were recorded. A great number of these runs displayed bimodal characteristics of the spreading function at high frequencies. It was found that in general, the frequency-integrated directional width tends to broaden as the water shoals and when refraction effects are negligible. This is attributed to wave-wave interactions that become pronounced in shallow water. The same directional width showed, also, a tendency to increase with increasing peak frequency of the sea state spectrum. The behavior of the kurtosis of the spreading function was also examined. It was found that for higher frequencies this index tends to increase in wave spectra above a certain sea severity threshold.

• 수산해양기술연구
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• 제41권1호
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• pp.1-8
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• 2005

여수 돌산도의 동쪽 승망 어장 주변 해역을 중심으로 수온, 해저지형, 조류의 이동과 어획량을 조사하여 대상어장의 환경을 평가하였다. 또한 동 해역의 5개 정점에서 체장 22.0${\sim}$51.0cm의 숭어 160마리를 5회에 걸쳐 표지 방류하여 숭어의 이동방향을 파악하였다. 그 결과를 요약하면 다음과 같다. 1. 승망 어장에서 수온은 2월에 가장 낮고, 3월 이후 점점 상승하여 8월에 최고가 되며 9월부터 다시 하강하여 10월과 11월 사이에 급격하게 하강하였으며, 그 범위는 6.9${\sim}$27.4$^{\circ}C$이었다. 월별 숭어의 여획량은 3월부터 9월까지 양호하였으나, 10월과 11월 사이에 수온이 급격하게 하강하면서 어획량이 줄어들었다. 숭어는 연중 수온범위 6.9${\sim}$27.4$^{\circ}C$에서 어획되었으며, 특히 수온이 높아지기 시작하는 15.0${\sim}$25.0$^{\circ}C$의 범위에서 어획이 양호하였다. 2. 돌산도 동쪽 해역의 승망 어장에 분포한 등심선은 승망 어구가 설치되어 있는 연안쪽에는 6${\sim}$13m의 범위로 조밀하게 분포하고, 어장의 외해쪽에는 14m 이상의 넓은 간격으로 분포하고 있다. 3. 승망 어구가 설치되어 있는 연안쪽에서 낙조류와 창조류는 해안선을 따라 각각 남류와 북류하였다. 연안 외해측에서 조류는 우전환류가 나타나 낙조류는 남동류로 평균유속은 43cm/secdldjTdmsk, 창조류는 북서류로 평균 유속은 25cm/sec이었다. 4. 숭어의 표지방류 후 재포율은 평균 9.4%로 높게 나타났으며, 어장별 재포율은 계동 연안이 33.3%로 다른 연안어장보다 높았다. 돌산도 연안에서 숭어의 이동은 육수의 유입이 많은 내만을 찾아 이동한 경향이 뚜렷하였으며, 남하이동보다는 북상이동하는 경향을 나타내고 있다.

• 수산해양기술연구
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• 제49권3호
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• pp.227-237
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• 2013

In Jeju Island, red sea bream is mainly caught by long line with a live squid as bait. The movements of artificial jigs in the fishery are supposed to be an important factor for catching the target organism as well as bait. To develop new fishing method for long line fishery, movements of the bait which was squid were tried to be characterized. In a water tank experiment, a live squid was hooked by a fish hook attached to a model long line. And then movements of squids in the water tank were recorded for 20 minutes by a video camera. Recorded movement of the squid was just periodically up-and-down moving, with a dominant frequency of 0.125Hz, and amplitude of 10.8cm.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제3권1호
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• pp.33-39
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• 1999

A two-dimensional numerical experiment and field observations were conducted to evaluate changes in sea water movement and the water quality environment related to comprehensive projects of waterfront development around Kwangyang Bay on the south coast of Korea. Tidal flow velocities, especially in the western part of the bay, were considerably slower as a result of the development projects. Accordingly, the seawater exchange ratio reduced from 38.7% to 26.3%. The impact of dredging work on the water quality environment was much stronger than expected. Furthermore, after the completion of the industrial parks and container-exclusive wharfs, COD from the waste water treatment plant will be dispersed extensively into the adjacent water at a level of less than 0.1 mg/l for up to 142.5 $\textrm{km}^2$. Therefore, consistent monitoring and management of the water quality environment is strongly recommended.

• Korean Journal of Geomatics
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• 제2권2호
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• pp.91-98
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• 2002

Lands along the coast may be submerged in high water because of erosion by sea water, collapsing by itself, excavation by animals, and by tidal movement. From a cadastral point of view, some mistakes in registering a parcel located along the coast may cause the parcel to seem to be collapsed. Therefore, geological, physical oceanographic, and cadastral and topographic investigation are necessary to verify that the submerged land in high water collapsed after it was registered. This paper presents a cadastral and topographic investigation for proving a parcel has collapsed under the sea after registered. In this study, cadastral records and the boundary on cadastral maps were examined carefully to find any errors in them. If the topographic maps were drawn when the parcel was registered, it is good proof of topography of the land at that time. Topographic maps drawn recently were compared to those in the 1900s and in 1970s. In conclusion, cadastral records and maps as well as topographic maps play an important role in proving whether lands along the coast were collapsed or not.

• 한국해양학회지:바다
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• 제16권1호
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• pp.1-13
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• 2011

황해저층냉수는 지난 동계의 차고 건조한 바람에 의해 생성되어, 하계에 황해 중앙골을 따라 남하하는 것으로 알려져 있다. 동중국해 북부해역에서 황해저층냉수의 특성과 거동을 파악하기 위해 2003년부터 2009년까지 하계에 관측한 자료를 분석하였다. 수괴분석을 통해 본 연구해역에 영향을 미치는 황해저층냉수를 새롭게 정의하여 북서저층냉수라고 명명하였고, 수온 $13.2^{\circ}C$ 이하, 염분 32.6~33.7 psu와 밀도 $24.7{\sim}25.5\;{\sigma}_t$로 특성지었다. 지형류 계산에 의해 연구해역에서 북서저층냉수는 약 2 cm/s 이하의 속도로 남하하는 것으로 추정하였다. 정의한 북서저층냉수는 수온의 범위와 자지하고 있는 영역에서 연간 변동을 보이며, 이러한 변동은 이전 해 동계 황동중국해의 표층수온의 변화와 밀접한 관련이 있었고, 동계 표층수온의 변화는 동계 기온에 의한 영향이 지배적임을 확인하였다. 동계 동중국해 표층수온은 북극진동 지수와 높은 상관성을 보이며, 동계의 북극진동이 음일 때 동중국해 표층수온이 하강하였고, 이러한 영향으로 북서저층냉수 세력이 동중국해 북부 해역까지 저수온을 보이면서 확장하였다. 동 연구는 동계의 북극진동지수, 황동중국해 겨울철 표층수온, 동중국해 북부의 북서저층냉수가 역학적으로 관련이 있음을 보였고, 이를 바탕으로 하계 동중국해 북부해역에서 저층냉수의 거동을 유추할 수 있을 것으로 사료된다.

• 대한공간정보학회지
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• 제23권1호
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• pp.65-71
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• 2015

여름철이 되면 매년 남해안에서 발생되고 있는 적조현상은 양식장을 운영하는 어민들에 막대한 피해를 주고 있으며 이를 방재하기 위한 노력이 다각도로 진행되고 있다. 특히 위성영상을 이용한 적조 모니터링은 발생해역 전반에 걸친 적조발생자료를 취득할 수 있어서 방재 계획수립에 중요한 정보를 제공하여 줄 수 있다. 따라서 본 연구에서는 천리안 GOCI영상을 이용하여 하루 중 적조의 확산과 감소를 모니터링할 수 있는 결과를 제시하기 위하여 경상남도 남해안 지역을 선정하고 2013년(8월 12일), 2014년(9월 11일) GOCI영상자료를 분석한 결과 다음과 같은 결론을 얻었다. 남해안 해역의 적조발생 패턴은 오전에 거제도 남부해역에서 출현하여 점점 더 확산되다가 오후 1시에 최대가 되고 그 후 서서히 감소되는 경향을 보여주었다. 또한 하루 중 적조의 중심 이동은 거제시 남부해역에서 적조가 시작하여 서쪽으로 이동하다가 정오를 기하여 다시 동쪽으로 이동하는 경향을 보여주었다. 향후 적조 생물의 특성과 해수유동, 태양 일조량, 그리고 해수온도 등 많은 요인에 대한 추가적인 연구가 필요하다고 판단되지만, GOCI 영상을 이용한 적조이동 모니터링은 적조의 확산과 이동을 예측하여 방재하고 관리하는데 매우 중요한 정보가 될 것으로 생각된다.

• 수산해양기술연구
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• 제46권3호
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• pp.232-238
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• 2010

The moving ranges and behavior of four wild abalones, Haliotis discus hannai, were measured by an acoustic telemetry technique. The shape of the sea bottom of the experimental area was surveyed by a bathymetry system and three self-recording type acoustic receivers were used for monitoring the behavior and measuring the movement range. The abalones (WA1-WA4) attached acoustic tags were released and measured the movement during ten months. Three abalones (WA1, WA3 and WA4) were successively detected around the released point during the experiment and were moved to the V2 area where water depth is deeper than the V1 area. The change of inhabitation depth was also detected from the depth sensor of WA4. As the result, abalones were moved to deeper water area accordance with the decrease of the water temperature. The moved ranges of abalones were approximately 200 - 400m from the release point.