• 수산해양기술연구
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• 제13권1호
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• pp.11-15
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• 1977

1977~76년에 부산수산대학의 오태산호를 사용하여 북서태평양의 소련 Kamchatka 반도와 Kurile열도 근해에서 해양 관측, 음향 측심 및 해류 조사를 실시한 자료를 해석하고, 해수유동과 해저지형과의 관련성 등에 관하여 검토하였다. Kamchaka 반도 동방의 대륙붕은 넓게 확장되어 그 폭은 약 75km에 달하고 그 경사는 완만하다(1~2。). 이 대륙붕은 Paramushir도 동방에서 폭이 좁아져서 약 36km가 되고 경사가 급해진다. Onekotan만 동쪽 약 20mile 해역에는 대륙붕이 조금 짤라져 해삼 모양의 솟은 곳이 있고, 그 단면은 평두해산과 비슷하다. Kurile열도 동방 Oyashio 해류 유역에서 직접 측류한 결과는 약 1kt로서 해류의 역학계산으로 얻은 유속 0.5~0.7kt 보다 조금 빨랐다. Oyashio 해류 동쪽 가장자리에는 강한 해류와 개속된 대소 규모의 좌선 및 우선 소용돌이가 줄지어 있다.

• 수산해양기술연구
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• 제55권4호
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• pp.335-348
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• 2019

We found ten species of larvae belonging to the family Pleuronectidae as a result of analysis on ichthyoplankton collected monthly from the East Sea, Yellow Sea, Korea Strait and East China Sea between February 2016 and May 2018 using bongo net. The ten species of pleuronectid larvae were divided into three groups in morphology. Group A had three or four bars on the lateral side of the tail: Glyptocephalus stelleri, G. kitaharae, Pseudopleuronectes yokohamae, and Hippoglossoides dubius. Group B had a row of melanophores along the dorsal and ventral side of tail: Cleisthenes pinetorum, Eopsetta grigorjewi, Dexistes rikuzenius, and Platichthys bicoloratus. Group C had dense melanophores which are covering trunk and tail entirely except caudal peduncle: Platichthys cornutus and Platichthys japonicus. The three groups did not associate with previous molecular phylogenetic studies except for the G. stelleri and G. kitaharae of the group A.

• 자원환경지질
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• 제29권3호
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• pp.369-380
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• 1996

In order to determine the emplacement time and stratigraphic position of basaltic rocks in the central part of Pohang basin, palaeomagnetic investigations were conducted on 111 samples collected from 6 sites. Formation mean built from site-mean ChRM directions is $d=340.7^{\circ}$, $i=52.2^{\circ}$ (${\alpha}_{95}=6.0^{\circ}$, k=91) in the geographic coordinates. If "tilt" correction is applied regarding the plane perpendicular to the side walls of columnar joint as palaeohorizon, the formation mean becomes $d=328.7^{\circ}$, $i=43.8^{\circ}$ (${\alpha}_{95}=17.1^{\circ}$, k=13). It is to be noticed that the formation mean is deflected significantly (about $20{\sim}30^{\circ}$) counterclockwise from the Tertiary reference geomagnetic field of Eurasia, independent of "tilt" correction. This situation is very different from that of clockwise rotation of ChRM directions which has been ubiquitously observed in other Tertiary basins of south Korea, and indicates sinistral regional simple-shearing during the emplacement times of the basaltic rocks. Considering previous palaeomagnetic and AMS (anisotropy of magnetic susceptibility) data from other Tertiary regions of south Korea, the time of this sinistral shearing should be 15 Ma or directly thereafter, and this time point represents inversion from extensional to compressional tectonic regime. Magnetic foliation data obtained in this study indicate WNW-ESN compression during or directly after emplacement of the basaltic rocks, while it has known from regional tectonic study that the time of the WNW-ESN compression is about 15 Ma, when SW Honshu was rotated and the Korean strait was narrowed.

• 한국수산과학회지
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• 제27권1호
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• pp.47-58
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• 1994

Field observation and numerical experiments with a two-dimensional depth-integrated model were undertaken in order to investigate some of the effects on the flow structure resulting from the construction of a bridge connecting Kohung Peninsula and the Narodo Islands on the southern coast of Korea. Tidal currents passing through the straits between the Narodo Islands showed that, although the phase lagged one hour behind that passing through the strait between Kohung Peninsula and Naenarodo Island, it still kept strong flows of more than 80cm/sec near the bottom. The seawater temperature and salinity within the study area seemed to be higher southward but uniform vertically. The results of the drogue experiments in the straits between the Narodo Islands showed that the drogues moved northward of Sayangdo in the early part of the flood tide, but southward in the late part of the flood tide and finally stopped a mile from the east coast of Surakdo. On the other hand, the numerical computation showed that the flow structures after construction of the bridge piers were basically in line with those before construction of the bridge piers, except for the slight variations of velocities in the vicinity of the bridge piers. A large scale clockwise circulation has been confirmed in the south area of Namsungri of Kohung Peninsula from the computational results of tide-induced residual currents. Referring to these computational results, the impact category on the flow structures due to the bridge piers construction has been estimated to be within around 2km. The results were in good agreement with the field observations.

• Journal of the korean society of oceanography
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• 제32권4호
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• pp.171-180
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• 1997

Daily mean sea level variability and its response to atmospheric pressure along the coasts of the northwestern Pacific Ocean are investigated. Daily values of sea level and atmospheric pressure covering the period 1976-1986 from 72 stations are analyzed. The sea level and the air pressure in all the data set have a definite seasonal signal, and higher frequency oscillations at time scales of several days to several weeks are also observed. Among the short-period oscillations of sea level with periods shorter than six months, the period of around 3 or 4 months is dominant in most study stations. According to the statistical analysis of sea level and air pressure, the length scale of sea level variability is smaller than that of air pressure for the present study area. The overall variability of sea level is found to be the smallest around Hokkaido, Japan and the largest in the China coasts. Large short-period (< 6 months) sea level variability is found in the southern coasts of China and Hokkaido, and large long-period (> 6 months) variability in the southern coasts of Japan and Korea along Tsushima Current and Kuroshio. The patterns of air pressure are very similar to those of sea level. The air pressure field is found to account for 31% of the overall sea level variability in the study area. Conside.ins the fact that the results (40%) of Pang and Oh (1995) were obtained through monthly sea level, the present result implies that the short-period sea level variability is less affected by air pressure. Generally the sea level response to air pressure are found to be isostatic, but significantly nonisostatic for the periods around 4 months and for those of 2 to 4 days. In particular, nonisostatic response for higher frequencies seem to be due to the restrictions to water transport necessary for barometric responsein the Korea Strait.

• 환경생물
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• 제36권4호
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• pp.687-693
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• 2018

The active development of the global marine trade industries has been known to increase the inflows of marine invasive species and harmful organisms into the ecosystem, and the marine ecological disturbances. One of these invasive species, Ciona robusta, has now spread to the Korea Strait, the East Sea, and Jeju Island in connection with the climate change but not the Yellow Sea in Korea. Currently, the spread and distribution of C. robusta is increasingly damaging aquaculture and related facilities. Therefore, this study aims to identify the spread of C. robusta and potential habitats and to secure a data for the prevention of effective management measures due to climate change as well as damage the reduction in future through the prediction of spread. We used environmental variables in BioOracle. Also, the potential habitat and distribution of C. robusta was predicted using MaxEnt, a species distribution model. Two different RCP scenarios(4.5 and 8.5) were specified to predict the future distributions of C. robusta. The results showed that the biggest environmental factor affecting the distribution of C. robusta was the salinity as well as the highest distribution and potential habitats existent in the East Sea and around Jeju Island.

• 해양환경안전학회지
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• 제25권3호
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• pp.259-268
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• 2019

Even if only two ships are encountered, a collision may occur due to the mistaken judgment of the positional relationship. In other words, if an officer does not know a target ship's intention, there is always a risk of collision. In this paper, the experiments are conducted to investigate how the intention affects the action of collision avoidance in cooperative and non-cooperative situations. In non-cooperative situation, each ship chooses a course that minimizes costs based on the current situation. That is, it always performs a selfish selection. In a cooperative situation, the information is exchanged with a target ship and a course is selected based on this information. Each ship uses the Distributed Stochastic Search Algorithm so that a next-intended course can be selected by a certain probability and determines the course. In the experimental method, four virtual ships are set up to analyze the action of collision avoidance. Then, using the actual AIS data of eight ships in the strait of Dover, I compared and analyzed the action of collision avoidance in cooperative and non-cooperative situations. As a result of the experiment, the ships showed smooth trajectories in the cooperative situation, but the ship in the non-cooperative situation made frequent big changes to avoid a collision. In the case of the experiment using four ships, there was no collision in the cooperative situation regardless of the size of the safety domain, but a collision occurred between the ships when the size of the safety domain increased in cases of non-cooperation. In the case of experiments using eight ships, it was found that there are optimal parameters for collision avoidance. Also, it was possible to grasp the variation of the sailing distance and the costs according to the combination of the parameters, and it was confirmed that the setting of the parameters can have a great influence on collision avoidance among ships.

• 무역학회지
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• 제48권4호
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• pp.149-168
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• 2023

기명식 선하증권과 해상화물운송장을 영미법과 우리나라법 그리고 해상운송관련 국제협약을 고찰하여 분석한 결과 기명식 선하증권은 영국이 1992년 해상화물운송법을 제정하기 전에는 기능에서 국가 간 차이가 있었으나 동법 제정 후 우리나라와 미국, 영국 모두에서 동일한 법적 지위와 기능을 가지게 되었다. 기명식 선하증권은 세 국가 모두에서 화물수취의 영수증, 운송계약의 증거기능 뿐만아니라 지시식 선하증권과 같은 권리증권성을 가지고 있다. 해상화물운송장은 세 국가 모두에서 계약적·법적 지위가 같았다. 즉 위탁화물을 운송인이 수취했다는 영수증이며, 운송계약의 증거이다. 다만 비유통성이고, 수하인의 신분확인만으로 운송인이 화물을 수하인이나 그 대리인에게 인도할 수 있으며, 해상화물운송장 양도·양수를 통해 화물에 대한 소유권을 취득하거나 해상운송인에 대한 법적 권리를 취득할 수는 없다.

• 해양환경안전학회지
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• 제29권6호
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• pp.576-586
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• 2023

남강댐 하류역에 위치한 사천만, 진주만, 강진만에서 가화천 방류에 따른 담수 배제의 분배 특성을 평가하기 위하여 입자추적 수치실험을 실험하였다. 가화천을 통해 3개의 방류조건(무방류, 강우시 방류, 홍수시 방류)에서 입자 1000개를 투여하여 노량수도, 대방수도, 창선해협으로 빠져나가는 입자의 수를 비교하였다. 가화천을 통한 방류량이 늘어날수록 노량수도로의 입자 분배율이 증가하고, 대방수도로의 분배율이 감소하는 것을 확인할 수 있었다. 즉, 평소에는 가화천 하류에 위치한 물질의 약 95%가 대방수도를 통해 빠져나가다가, 강우에 의해 남강댐의 방류량이 증가하면서 노량수도로의 분배율이 증가하며, 홍수시에는 노량수도로의 입자 분배율이 45.5% 까지 증가하는 것을 확인할 수 있었다.

• 한국해양환경ㆍ에너지학회지
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• 제13권3호
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• pp.151-164
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• 2010

남해의 여수와 돌산도 사이에 위치하는 협수로의 해양환경과 식물플랑크톤 군집의 계절변동 특성을 파악하기 위해 2005년 9월에서 2006년 5월까지 30개 정점을 대상으로 4회에 걸쳐 현장조사를 실시하였다. 조사기간 동안 표층해 수의 수온, 염분 및 소광계수는 각각 $5.6{\sim}26.3^{\circ}C$, 25.36~33.92 psu 및 0.13~2.13의 범위를 나타내었다. 수온은 여름과 봄에 가막만에서 높고, 가을과 겨울은 여수해만에서 더욱 높았다. 염분은 하수처리 배출구 인근해역을 제외하면 조사기간 동안 전 해역에서 균일한 분포를 나타내었다. 소광계수는 여수해만보다 가막만과 하수처리 배출구 인근 해역에서 높아 더욱 혼탁한 해수특성을 나타내었다. 식물플랑크톤은 총 51속 99종이 확인되었으며, 여름과 가을에 다양한 종 조성을 나타내었으나 중심목 규조류의 비율이 높은 겨울과 봄은 상대적으로 빈약한 종수를 보였다. 계절별 우점종은 여름에 Skeletonema costatum과 Chaetoceros curvisetus, 가을과 겨울은 Eucampia zodiacus, 그리고 봄은 Chaetoceros affinis와 Thalassionema nitzschioides로 나타났다. 식물플랑크톤 현존량과 Chl-$\alpha$ 농도는 각각 $0.2{\times}10^4{\sim}296{\times}10^4\;cells\;L^{-1}$와 $1.94{\sim}22.12\;{\mu}g\;L^{-1}$의 범위를 보였으며, 하계 가막만에서 월등히 높은 값을 나타내었다. 주성분 분석결과에 따르면, 돌산도 북부해역은 해양환경과 식물플랑크톤 군집특성으로부터 2개 또는 3개의 해역으로 세분되는 것으로 나타났다.