• 수산해양교육연구
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• 제12권2호
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• pp.152-163
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• 2000

Floating resin pellets including plastics were surveyed from 7 coastal beaches near Young-il Bay during summer and winter season on 1998 ~ 2000 year. Plastic fabrication materials in the survey were founded with 6 items using the following; resin pellets, plastic debris, styrofoams, cigar filters, wood pieces and charcoals. The results deduced in the areas are as follows: 1. The seasonal variability of the all debris is revealed that summer season were remarkably larger than those of winter. This is deduced it is attributed to meteorological effects, e.g, the seasonal wind strength, current vectors and resorts of crowded people for beach enjoy. And the distribution of plastic debris is Pohang Songdo $12.9ea/m^2$, Pohang Bookbu $8.8ea/m^2$, Togoo $4.9ea/m^2$, Chilpo $3.2ea/m^2$, Hwajin $1.4ea/m^2$, Wolpo and Guryongpo $0.8ea/m^2$ respectively. 2. Compared with each beaches, Songdo beach, northern part beach of Pohang city and Togoo beach have higher densities than those of the others. Especially, the highest densities of all debris were discovered in the Songdo beach of Pohang city. 3. The change of density over the whole year was similarly distributed in quantities and fabrication materials. 4. These surveys were founded that the most parts of plastic debris materials were made up with PE and PP.

• 한국해양공학회지
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• 제37권4호
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• pp.145-157
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• 2023

Due to a recent increase in maritime activities in South Korea, the frequency of maritime distress is escalating and poses a significant threat to lives and property. The aim of this study was to validate a drift trajectory prediction technique to help mitigate the damages caused by maritime distress incidents. In this study, OpenDrift was verified using satellite drifter data from the Korea Hydrographic and Oceanographic Agency. OpenDrift is a Monte-Carlo-based Lagrangian trajectory modeling framework that allows for considering leeway, an important factor in predicting the movement of floating marine objects. The simulation results showed no significant differences in the performance of drift trajectory prediction when considering leeway using four evaluation methods (normalized cumulative Lagrangian separation, root mean squared error, mean absolute error, and Euclidean distance). However, leeway improved the performance in an analysis of location prediction conformance for maritime search and rescue operations. Therefore, the findings of this study suggest that it is important to consider leeway in drift trajectory prediction for effective maritime search and rescue operations. The results could help with future research on drift trajectory prediction of various floating objects, including marine debris, satellite drifters, and sea ice.

• 한국해양환경ㆍ에너지학회지
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• 제4권3호
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• pp.65-73
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• 2001

본 논문에서는 현수선 모델에 기초를 둔 해석방법을 사용하여 부유쓰레기 차단막에 작용하는 흐름에 의한 장력 및 항력을 계산하였다. 흐름에 의한 항력우 차단막의 법선방향으로만 작동하여 차단막에 걸리는 장력은 일정하다고 가정하였다. 계산 모델로 차단막이 흐름방향과 대칭으로 설치된 경우와 비대칭으로 설치된 경우를 다루었다. 형상계수와 설치각도와 같은 차단막의 설치형상을 바꿔가면서 차단막에 작용하는 장력과 항력의 변화를 살펴보았다 계산 결과는 형상계수가 증가함에 따라 장력계수도 커지며 형상계수가 큰 범위에서는 장력계수의 증가폭이 커짐을 보여주고 있다 또한 차단막을 흐름방향과 비대칭으로 설치하였을 때 경사각도를 증가시키면 장력계수가 줄어든다는 사실을 발견하였다 계산모델은 한강 지류인 탄천에 설치한 길이 200m의 부유쓰레기 차단막에 적용하였다. 계산결과에 의하면 차단막 양 끝단에 설치한 앵커블록이 견딜 수 있는 최대 흐름속도는 2m/sec이다.

• 한국해양환경ㆍ에너지학회지
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• 제4권3호
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• pp.74-80
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• 2001

최근 연안 해역에서의 대규모 어업 활동과 경제개발로 인한 전반적인 산업화 현장의 확대, 그리고 생활 수준의 향상에 따른 여가 활동의 증가 등 다양한 요인에 의해 해저면의 침적폐기물, 폐각류, 오염 퇴적물 등 각종 오염 물질의 배출이 해양 자체의 정화 능력을 넘어서는 심각한 상태에 처해 있는 실정이다 이러한 해저면 폐기물을 그대로 방치해 두게 되면 시간이 경과함에 따라 저서 생태계의 교란을 초래하게 된다. 따라서, 해저면 폐기물에 의한 해양 생태계의 교란을 예방하고, 오염된 해양 환경을 복원하기 위해서는 해저면에 대한 수중침적 폐기물 실태조사를 실시하여 오염실태를 파악하고, 이들 관련자료를 체계적으로 관리 운영함으로서 효율적인 폐기물 수거 방안의 수립을 지원할 수 있는 체계를 갖추어야 한다. 이의 일환으로 본 연구에서는 항 내 수중침적 폐기물의 실태를 파악하기 위한 조사 방법을 확립하고, 이를 토대로 국내 연안의 주요 항만 및 어항에 대한 항 내 수중침적 폐기물 분포 현황을 조사하였다.

• 한국제4기학회지
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• 제19권2호
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• pp.55-58
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• 2005

A 120-cm core recovered from Lake Hovsgol, the northern Mongolia provides evidence for climate variability since the Marine Isotope Stage 3, representing a sharp lithological change. The lowermost part of the core consists of diatom-barren calcareous silty clay without coarse sands, framboidal pyrite, and biogenic components deposited during the MIS 3. Following the last glacial maximum, in-situ moss is included in the sediments, as lake-level was retreated by cold and dry environment with low precipitation. The AMS radiocarbon ages of the plant fragments match a marked lithologic boundary between 14,060 and 14,325 $^{14}C$ yr BP. The contents of coarse sands abruptly increase, indicating probably wind-derived sandy dust or coarse grains contributed from floating icebergs. And abundant framboidal pyrite grains were deposited in an anoxic environment, as reflected by high accumulation of organic matters at a low lake stand. During the deglaciation, quantities of coarse sands, ostracod, shell fragments, framboidal pyrite, and diatom markedly varies by regional and global scale climate regimes. Some allochthonous coarse sands were probably ice-rafted debris derived from floating icebergs. A rapid increase in diatom productivity probably marked the onset of Bolling-Allerod warming. Subsequent high concentration of framboidal pyrite probably represents a dry and cold condition, such as Younger Drays events. Consistent warm period with high precipitation at Holocene is documented by diatomaceous clayey ooze without framboidal pyrite, coarse sands, and ostracod.

• 한국제4기학회:학술대회논문집
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• 한국제4기학회 2005년도 추계학술대회
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• pp.34-39
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• 2005

A 120-cm core recovered from Lake Hovsgol, the northern Mongolia provides evidence for climate variability since the Marine Isotope Stage 3, representing a sharp lithological change. The lowermost part of the core consists of diatom-barren calcareous silty clay without coarse sands, framboidal pyrite, and biogenic components deposited during the MIS 3. Following the last glacial maximum, in-situ moss is included in the sediments, as lake-level was retreated by cold and dry environment with low precipitation. The AMS radiocarbon ages of the plant fragments match a marked lithologic boundary between 14,060 and 14,325 $^{14}C$ yr BP. The contents of coarse sands abruptly increase, indicating probably wind-derived sandy dust or coarse grains contributed from floating icebergs. And abundant framboidal pyrite grains were deposited in an anoxic environment, as reflected by high accumulation of organic matters at a low lake stand. During the deglaciation, quantities of coarse sands, ostracod, shell fragments, framboidal pyrite, and diatom markedly varies by regional and global scale climate regimes. Some allochthonous coarse sands were probably ice-rafted debris derived from floating icebergs. A rapid increase in diatom productivity probably marked the onset of Bolling-Allerodwarming. Subsequent high concentration of framboidal pyrite probably represents a dry and cold condition, such as Younger Drays events. Consistent warm period with high precipitation at Holocene is documented by diatomaceous clayey ooze without framboidal pyrite, coarse sands, and ostracod.