• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.05a
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• pp.146-147
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• 2015

현재 선박이나 교각 해양플랜트는 많은 철판으로 구성이 되어 있다. 특히 해양플랜트와 선박에는 오랜시간 바다에 있으므로 각종 해양생물들이 붙어 번식을 한다. 이러한 해양생물은 선박의 속도 및 연료 소모에 상당한 영향을 미친다. 그러므로 선박이나 해양플랜트 구조물은 정기적으로 벽면에 서식하는 해양생물을 제거하고 있으며 이러한 제거과정과 도장을 다시하는 과정에서 작업자들에게 위험이 따른다. 본 연구는 선박이나 해양플랜트와 같은 철로된 구조물의 위험한 작업을 대신할 로봇의 기반인 철판 벽면을 이동하는 로봇을 연구하였다. 현재 많은 벽면 로봇들이 연구되고 있다. 영구자석 또는 전자석 휠을 사용하거나 공압을 이용하여 수직벽면에서 작업을 한다. 특히 공압 방식을 많이 사용하였는데 수직벽면에 로봇이 밀착될 만큼 강한 공압이 필요하게 되기 때문에 부가적인 장치가 많이 필요하다. 본 논문에서는 부가적인 장치를 최소화하고 효과적인 동작을 하기위해 전자석 방식을 선택 하였으며 간편하게 선박의 수직벽면을 작업할 수 있는 전자석 방식의 4 륜 로봇을 개발하고자 한다. 선박의 수직벽면 작업용 4 륜구동 로봇을 전자석을 이용하여 수직벽면에 부착할 수 있도록 설계하였으며 자력의 세기와 방향을 제어하여 로봇이 선박의 수직면에 밀착되어 자유롭게 이동이 가능하도록 개발 하고자 한다.

• Korean Journal of Environmental Biology
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• v.39 no.1
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• pp.88-99
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• 2021

In this study, a land-based marine closed mesocosm (LMCM) experiment was performed to objectively assess the initial stability of an artificial ecosystem experiment against biological and non-biological factors when evaluating ecosystem risk assessment. Changes in the CV (coefficient of value) amplitude were used as data to analyze the stability of the experimental system. The CV of the experimental variables in the LMCM groups (200, 400, 600, and 1,000 L) was maintained within the range of 20-30% for the abiotic variables in this study. However, the difference in CV amplitude in biological factors such as chlorophyll-a, phytoplankton, and zooplankton was high in the 600 L and 1,000 L LMCM groups. This result was interpreted as occurring due to the lack of control over biological variables at the beginning of the experiment. In addition, according to the ANOVA results, significant differences were found in biological contents such as COD (chemical oxygen demand), chlorophyll-a, phosphate, and zooplankton in the CV values between the LMCM groups(p<0.05). In this study, the stabilization of biological variables was necessary to to control and maintain the rate of changes in initial biological variables except for controllable water quality and nutrients. However, given the complexity of the eco-physiological activities of large-scale LMCMs and organisms in the experimental group, it was difficult to do. In conclusion, artificial ecosystem experiments as a scientific tool can distinguish biological and non-biological factors and compare and analyze clear endpoints. Therefore, it is deemed necessary to establish research objectives, select content that can maintain stability, and introduce standardized analysis techniques that can objectively interpret the experimental results.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.331-332
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• 2001

발전소 등에서 배출되는 온배수는 해수의 수은을 변화시키며, 이로 인해 해양생태계에 많은 영향을 미친다 (Naylor, 1965). 발전소 온배수에 의해 27.2$^{\circ}C$~31.$0^{\circ}C$의 수온상승은 부착성 군집구조 가 우세하며, 37$^{\circ}C$이상의 수온에서는 수주고둥 및 따개비류를 제외한 모든 동ㆍ식물이 소멸한다 (Suresh et al., 1993). 또한, Ahamed et al. (1992)는 발전소 온배수의 영향을 받는 해역에서는 소수의 수주고둥과 남조류를 제외하고 해양생물 출현이 없었다고 보고하였다. (중략)

• 한국지구과학회:학술대회논문집
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• 2010.04a
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• pp.137-137
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• 2010

해양 혼합층은 해양-대기 간의 상호작용을 통해서 기후 변화 뿐만 아니라, 식물성 플랑크톤 분포와 같은 생물학적 측면에도 큰 영향을 줄 수 있기 때문에 매우 중요하다. 따라서 본 연구에서는 우리나라 장단기 기후변동에 많은 영향을 주는 북동아시아 근해 내에서의 혼합층 깊이의 시공간 변동을 분석하였다. 기존에 해양 관측 자료가 절대적으로 부족했던 점을 극복하기 위해 2000년부터 전구 해양에서 실시간으로 수집되기 시작한 해양중층부이(ARGO) 자료를 활용하였다. 지금까지 제시되어 온 다양한 해양 혼합층 결정 기준 중 가장 널리 사용되고 있는 Levitus et al.(1997)의 기준을 적용하여 북동아시아 근해의 혼합층 깊이를 산출하였으며, 그 변화를 위도, 경도, 해안으로부터의 거리, 계절 등에 따라 분석하였다. 또한 계절적 변화에서 겨울철 해양 혼합층 변화의 역전이 나타나는 지역을 분석하였다. 이와 같은 분석결과는 추후 해양 혼합층 깊이 결정 방법에 대한 연구의 기초자료로 활용될 것으로 기대한다.

• Atmosphere
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• v.20 no.3
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• pp.379-386
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• 2010

Impact of global warming on the ocean environment is reviewed based on most recently published publications. The most significant impact of global warming on marine environment is due to the melting of mountain and continental glaciers. Ice melting causes slow down and/or shut down of thermohaline circulation, and makes hypoxic environment for the first time, then makes anoxic with time. This can cause decreasing biodiversity, and finally makes global extinction of animals and plants. Furthermore, global warming causes sea-level rise, soil erosion and changes in calcium carbonate compensation depth (CCD). These changes also can make marine ecosystem unstable. If we emit carbon dioxide at a current rate, the global mean temperature will rise at least $6^{\circ}C$ at the end of this century, as predicted by IPCC (Intergovernmental Panel on Climate Change). In this case, the ocean waters become acidic and anoxic, and the thermohaline circulation will be halted, and marine ecosystems collapsed.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.4
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• pp.280-286
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• 2007

In order to find out the effects of the anticyclonic eddy on the distribution of nutrients and chlorophyll concentrations in the Ulleung Basin during spring and summer, we measured temperature, salinity, nutrients, and chlorophyll from the surface to 200 m water depth at five stations in July 2005 and April 2006. In spring, surface mixed layer was very deep inside the eddy, about 200 m, but it was relatively shallow outside the eddy, about $20{\sim}60$ m. Inside of the eddy, nutrients in the surface waters were sufficient by supply from the deep layer, whereas outside of the eddy, they were fairly depleted due to the stratification in the surface layer. In spring, chlorophyll concentrations were relatively low inside of the eddy due to the deeper surface mixed layer compared with the euphotic depth, and the depth-integrated chlorophyll concentrations outside of the eddy were twice as much as those inside of the eddy. In summer, nutrients in the surface waters were completely depleted at all stations due to the well stratification in the surface layer. The typical distribution pattern of subsurface chlorophyll maximum was observed at all stations, and the depth-integrated chlorophyll concentrations inside of the eddy were almost twice as much as those outside of the eddy. The anticyclonic eddy appearing in the Ulleung Basin every year significantly affects the phytoplankton biomass, with the opposing effects in spring and summer; in spring, the anticyclonic eddy suppresses phytoplankton growth, but in summer, it enhances the phytoplankton biomass.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.366-368
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• 2000

연안 매립을 포함하는 방파제의 건설이나 호안의 건설은 자연적인 해류의 흐름을 방해하는 인위적 교란으로 나타나며 그에 따른 수력학적 변화에 의해 퇴적학적 특성은 물론 지형학적 변화를 유발하게 된다. 이러한 물리적 환경의 변화가 저서생물의 유생의 분포, 먹이입자의 퇴적작용, 그리고 퇴적상의 변화를 초래하고 결국 저서동물군집의 구조에 변화를 주게 된다(Seys et al., 1994). (중략)

• Journal of Ocean Engineering and Technology
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• v.26 no.2
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• pp.14-19
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• 2012

There are insufficient data to consider the effect zone for the marine life of coastal fisheries, because no standard has been defined for the sound level of marine life. In this study, equations for distance attenuation were used to determine the effect zone for oceanic noises. A reference noise level was divided into 4 parts to consider the characteristics of the fishes, and the effect zone of each reference noise level was determined. To increase the reliability of the effect scope, approximately 100 repetitions of blasting work split into several parts by the boring depth, the sound level of the source caused by an increase in weight, and the effect zone were calculated using the prediction equation. According to the prediction, the maximum distance of the effect zone was 4.92 km.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.4
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• pp.243-252
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• 2006

Influence of the increasing carbon dioxide concentration in seawater on various marine organisms is assessed in this article with regard to the impacts of anthropogenic $CO_2$ introduced into surface or deep oceans. Recent proposals to sequester $CO_2$ in deep oceans arouse the concerns of adverse effects of increased $CO_2$ concentration on deep-sea organisms. Atmospheric introduction of $CO_2$ into the ocean can also acidify the surface water, thereby the population of some sensitive organisms including coral reefs, cocolithophorids and sea urchins will be reduced considerably in near future (e.g. in 2100 unless the increasing trend of $CO_2$ emission is actively regulated). We exposed bioluminescent bacteria and benthic amphipods to varying concentrations of $CO_2$ and also pH for a short period. The ${\sim}l.5$ unit decrease of pH adversely affected test organisms. However, amphipods were not influenced by decreasing pH when HCl was used for the seawater acidification. In this article, we reviewed the biological adverse effects of $CO_2$ on various marine organisms studied so for. Theses results will be useful to predict the potential risks of the increase of $CO_2$ concentrations in seawater due to the increase of atmospheric $CO_2$ emission and/or sequestration of $CO_2$ in deep oceans.

• Korean Journal of Environmental Biology
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• v.18 no.1
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• pp.1-20
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• 2000

There are increasing evidences of climate change in the Antarctic and Arctic Oceans, especially elevated temperature due to the continuous burning of the fossil fuels and ultraviolet B(UV-B) flux within the ozone hole. Light-dependent, temperature-sensitive, and fast-growing organisms respond to these physical and biogeochemical changes. Polar marine phytoplankton, which are pioneer endemic species and important carbon contributors in the polar waters, are therefore highly suitable biological indicators of such changes. By virtue of light requirement, the primary producers are exposed to extreme seasonal fluctuations in temperature, photosynthetically active radiation, and UV radiation. Local environmental warming and increased UV-B radiation during ozone depletion may have profound effects on the primary producers that are primary carbon producers in the polar water. Small changes in climate temperature and solar radiation may have profound effects on the activity threshold of the polar phytoplanktion. To demonstrate biological response to the environmental changes, standardized representative natural and biological parameters are needed so that replicate samples (including controls) can be taken over extended periods of time. In this paper, we review general characteristics of polar phytoplankton, their environment, environmental changes in the polar waters, the effects on the environmental changes to the polar phytoplankton, and the importance of the polar phytoplankton to understand the global environmental changes. [Biological indicators, Global environmental change, Polar phytoplankton, UV].