• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.5
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• pp.535-541
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• 2019

The purpose of this study was to investigate the possibility of fishery in offshore wind farms and evaluate the risk linked to the presence of turbines and submarine cables in these areas. With this objective, we studied an offshore wind farm in the Southwest Sea and the current state of vessels in the surrounding National Fishing Port. The risk assessment criteria for 22 fishing gears and methods were set by referring to the fishing boats; thereafter, the risk was assessed by experts. The fishing gears and methods that could be safely operated (i.e., associated with low risk) in the offshore wind farm were: single-line fishing, jigging, and the anchovy lift net. The risk was normal so that it is possible to operate, but the fishing gears and methods that need attention are: the set long line, drifting long line, troll line, squid rip hook, octopus pot, webfoot octopus pot, coastal fish pot, stow net on stake, winged stow net, stationary gill net, and drift gill net. Moreover, the fishing gears and methods difficult to operate in the of shore wind farm (i.e., associated with high risk) were: the dredge, beam trawl, and purse seine. Finally, those associated with very high risk and that should not be allowed in offshore wind farms were: the stow net, anchovy drag net, otter trawl, Danish seine, and bottom pair trawl.

• Journal of Korea Port Economic Association
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• v.35 no.2
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• pp.77-92
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• 2019

As China's economic growth pole has shifted from the coastal area to the Midwest and the inland since the beginning of 2000, construction of China's inland ports was promoted in the coastal area. The inland port functions as offshore port, thereby streamlining import and export logistics and customs clearance and so on. The purpose of this study is to identify the competitiveness and potential of China's inland ports via functional and geographical classification, as well as SWOT-PEST analysis. According to the results of the study, inland ports can be functionally categorized as sea port-based, industrial-based, distribution-based and customs clearance-based. The majority of the sea port-based inland ports are located in the eastern part of China while industry-based and distribution-based inland ports are situated in the Midwest. On contrast, the inland ports in Northwest mainly perform the function of customs clearance to promote international trade with neighbouring countries. The inland ports in the eastern region have high competitiveness owing to a large volume of international trade in the region, whereas those in the Midwest have high potential. The 'One Belt to One Road' initiative proposed by the Xi's Government is expected to play a significant role in promoting the development of inland ports in the Midwest and border areas.

• Convergence Security Journal
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• v.17 no.5
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• pp.41-47
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• 2017

The Marine Environment Observation Information System supplies oceanographic information elements such as water temperature, chlorophyll, float, etc. based on satellite images to consumers. The data produced by the Korean marine environmental observatories are located in the coastal areas of Korea. But if the range is too far from a particular area of interest, due to distance or spatial constraints, the accuracy and up-to-dateness of the data can not be relied upon. Therefore, it is necessary to perform fusion and complex operation to solve the difference between the field observation and the marine satellite image. In this study, we develop a system that can process marine environmental information in the user's area of interest in the form of layered character (numeric) information considering the readability and light weight rather than the satellite image. In order to intuitively understand satellite image information, we characterize (quantify) the marine environmental information of the area of interest and we process the satellite image band values into layered characters to minimize the absolute amount of transmitted / received data. Also we study modular location-based interest information service method to be able to flexibly extend and connect interested items that diversify various observation fields as well as application technology to serve this.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.24-24
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• 2019

DMZ 및 접경지역은 지난 60여 년간 인간의 간섭을 받지 않아 세계적으로 우수한 생태계의 보고이며, 백두대간, 도서연안과 함께 한반도 3대 핵심생태축의 하나로서 한반도생태계보전을 위한 가장 중요한 지역이다. 이러한 DMZ 및 접경지역에 대하여 국내적 중요성 인식 제고뿐만 아니라 국제적으로도 중요생물다양성지역(KBAs)으로서의 가치인식을 위해 IUCN에서 제시하는 평가기준을 검토하고 이의 기준을 적용하여 DMZ의 생물다양성에 대한 국제적 가치정도 판단 및 중요생물다양성지역(KBAs)으로서의 보전방안을 수립하고자 한다. 첫째, DMZ 일대를 대상으로 서식하는 자생식물의 분포지역을 파악하여 DMZ 및 접경지역의 식물상은 18과 139속 367종 1아종 44변종 10품종 422분류군으로, 총 138과 613속 1,517종 8아종 217변종 58품종으로 총 1,800분류군으로 확인되었다. 본 연구대상지의 동부지역에서 가장 많은 1,482분류군, 중부지역은 1,225분류군, 서부지역은 1,080분류군으로 가장 적은수의 식물이 확인되었다. 둘째, DMZ 및 접경지역을 대상으로 객관적이고 정량적인 방법을 통한 DMZ 및 접경지역의 중요생물다양성지역(KBAs) 지정기준을 적용하여 개느삼, 금강초롱, 모데미풀 3종을 중요생물다양성지역(KBAs) 후보종으로 선정하였다. 후보종별로 분포예측 결과 전체 면적 $5,270.5km^2$ 중요생물다양성지역(KBAs) 지정을 제안하였다. 셋째, 지정기준을 통하여 선정된 DMZ 및 접경지역에 서식하는 주요 식물에 대한 국제적 가치를 판단하여 우리나라 상황에 맞는 중요생물다양성지역(KBAs)을 적용함으로써 효과적인 관리방안으로 투명하고 체계화된 국제적 기준으로 해당 지역 내의 생물종 다양성을 지속가능하게 보호하기 위한 구체적인 방향 설정 및 관리를 위한 노력이 이루어질 수 있도록 유도 할 수 있다. 수집된 자료를 통하여 중요생물다양성지역(KBAs)에 적합한 종을 중심으로 보호구역을 지정하고 국내적으로 중요한 지역적 멸종위기종에 대한 적용을 추가적으로 진행하여 식물다양성이 중요한 지역의 보호를 위한 우선순위 및 구체적 접근계획을 수립할 수 있을 것으로 판단된다. 국가적인 차원에서 DMZ 및 접경지역의 지속적인 조사를 통하여 중요생물다양성지역(KBAs)기준 적용에 필요한 기초자료를 충분히 수집하고 국내 환경에 부합하는 중요생물다양성지역(KBAs)기준 적용을 통하여 꾸준히 재평가하여 후속연구의 발판을 마련하여야 한다.

• Atmosphere
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• v.29 no.1
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• pp.87-103
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• 2019

This study introduces the overall characteristics of LOVECLIM version 1.3, the earth system model of intermediate complexity (EMIC), including the installation and operation processes by conducting two kinds of past climate simulation. First climate simulation is the equilibrium experiment during the mid-Holocene (6,000 BP), when orbital parameters were different compared to those at present. The overall accuracy of simulated global atmospheric fields by LOVECLIM is relatively lower than that in Coupled Model Intercomparison Project phase 5 (CMIP5) and Paleoclimate modelling Intercomparison Project phase 3 (PMIP3) simulations. However, surface temperature over the globe, the 800 hPa meridional wind over the mid-latitude coastal region, and the 200 hPa zonal wind from LOVECLIM show similar spatial distribution to those multi-model mean of CMIP5/PMIP3 climate models. Second one is the transient climate experiment from mid-Holocene to present. LOVECLIM well captures the major differences in surface temperature between preindustrial and mid-Holocene simulations by CMIP5/PMIP3 multi-model mean, even though it was performed with short integration time (i.e., about four days in a single CPU environment). In this way, although the earth system model of intermediate complexity has a limit due to its relatively low accuracy, it can be a very useful tool in the specific research area such as paleoclimate.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.2
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• pp.152-161
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• 2019

This research carried out a study on the job characteristics of the skipper of the coastal composite fishing vessels in order to find a way to prevent the ship collision caused by the highest human error among the marine casualty of fishing boats. Video observation was used as the research method in which six CCD cameras were installed on the vessel to collect image data and data extracted from the image were analyzed to derive the results of the functional activity of skipper according to the fishing operation process of experimental fishing vessel. The results are as follows. The working process of the experimental fishing vessel consisted of navigation for fishing ground, setting line, waiting for hauling line, hauling line and navigation to homeport. In these processes, the skipper was performing watchkeeping in the wheelhouse in which he carried out a single task, a dual task that performed two tasks simultaneously, and a triple task that performed two or more tasks simultaneously. In addition, one of the risk factors causing the collision was a no watchkeeping in the wheelhouse for navigating for fishing ground, waiting for hauling line, and hauling line at 25.4%, 64.6% and 0.3%, respectively among the marine casualty while drowsiness caused 1.2% of the marine casualty in navigating for fishing ground. Concurrent tasks that simultaneously perform two or more tasks that can overlook any other important duties while carrying out watchkeeping in the wheelhouse include 51.3% of navigation for fishing ground, 81.9% of setting line, 19.0% of waiting for hauling line, 87.9% of hauling, and 88.7% of navigation to homeport. The above concurrent tasks yielded an average of 66.1%. Experimental fishing vessels are required to focus on ship handling operations related to fishery operations, and the skipper is assigned more activities and attention to fishery related tasks. Therefore, it is considered desirable to build a collision prevention system that is appropriate to the characteristics of the skipper's work, escaping from transferring the responsibility of ship collision to the skipper completely.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.2
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• pp.187-207
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• 2019

In order to develop a high performance ocean model, we used Julia, a Just-In-Time compile language, and to obtain the solution of the momentum equation, we made the code to solve the Poisson equation by the Successive Over-Relaxation method. And then we made two models to test Julia calculation codes. First, a simple channel form is modeled to test constant source/sink conditions. Second, the simplified Yellow Sea was modeled to test tidal forcing, Coriolis forces, and the effect of vertical eddy diffusivity coefficients. The model has been tested with a total of eight cases in the two scenarios. As a result of the test, the depth-averaged current speed of the three cases in Scenario 1 converged perfectly to the theoretical value, and that showed well a vertical flow velocity gradient due to the bottom friction. Also, the result of Scenario 2 represented well the amphidromic points of Yellow Sea and the tidal characteristics of mid-western and southwestern coast of Korea. Therefore, it is considered that the ocean model using Julia language has developed successfully, this suggests that the ocean model has come to the stage of successful transition from a classical compile language to a Just-In-Time compile language.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.2
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• pp.73-87
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• 2019

Ocean waves are the driving force for the sediment transport and the beach process. However, wave actions are nonlinear and non-stationary, and the response of the beach is inconsistent in terms of reaction rate and magnitude. Therefore, the beach process is difficult to predict accurately. The purpose of this study is to identify the correlations between the shoreline change and ocean waves observed in the east coast of Korea. The relation of the beach width obtained from video monitoring at five sandy beaches and the wave data obtained from nearby wave monitoring at three points was analyzed. Although the correlations estimated over the whole data sets was not significant, the correlations estimated based on the seasonal period or wave conditions provided more noteworthy information. When the non-exceedance probability of the wave height was greater than 0.99, the wave period and beach width showed strong negative correlations. In case the non-exceedance probability of the wave period was greater than 0.99, the wave height and beach width showed strong negative correlations as well. Furthermore, the erosion rate of the beach width increased when the primary wave direction was close to normal to the coastline. Little significant seasonal or monthly change was found between the beach width and the wave, but it was greatly affected by intensive events such as typhoons. Thus, it is necessary to analyze in detail the wave height or period level explaining the change of beach width for more relevant and practical information.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.30 no.6
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• pp.286-297
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• 2018

In the present study, wave measurements at KOGA-W01 were analyzed and then the numerical wind waves simulations have been conducted to investigate the characteristics of wind waves in the Yellow sea. According to the present analysis, even though the location of the wave stations are close to the coastal region, the deep water waves are prevailed due to the short fetch length. Chun and Ahn's (2017a, b) numerical model has been extended to the Yellow Sea in this study. The effects of tide and tidal currents should be included in the model to accommodate the distinctive effect of large tidal range and tidal current in the Yellow Sea. The wave hindcasting results were compared with the wave measurements collected KOGA-W01 and Kyeockpo. The comparison shows the reasonable agreements between wave hindcastings and measured data, however the model significantly underestimate the wave period of swell waves from the south due to the narrow computational domain. Despite the poorly prediction in the significant wave period of swell waves which usually have small wave heights, the estimation of the extreme wave height and corresponding wave period shows good agreement with the measurement data.

• Journal of Life Science
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• v.29 no.2
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• pp.158-163
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• 2019

The purpose of this study was to isolate a new marine agarase-producing bacterium. Agarase can hydrolyze agar and agarose to produce agarooligosaccharides or neoagarooligosaccharides, which possess many physiological functions. Strain DH-3 was isolated from seawater collected from the coast of Yeosu at Jeollanam province, Korea. A 16S rDNA sequence analysis showed this strain to be Persicobacter sp. DH-3. Extracellular agarase was prepared from culture media of Persicobacter sp. DH-3 and used for characterization. Relative activities at 20, 30, 40, 50, 60, and $70^{\circ}C$ were 50, 55, 70, 100, 90, and 50%, respectively. Relative activities at pH 5, 6, 7, and 8 were 75, 100, 90, and 75%, respectively. The enzyme showed maximum activity at $50^{\circ}C$ in a 20 mM Tris-HCl buffer at pH 6. This enzyme could be useful, as agar is in liquid state at $50^{\circ}C$. Agarase activities were maintained at 80% or more for 2 hr at 20, 30, and $40^{\circ}C$. Thin layer chromatography analysis suggested that Persicobacter sp. DH-3 produced extracellular ${\beta}$-agarases as it hydrolyzed agarose to produce neoagarohexaose and neoagarotetraose. In addition, zymogram analysis confirmed that Persicobacter sp. DH-3 produces at least three agar-degrading enzymes with molecular weights of 45, 70, and 140 kDa. Therefore, it is expected that agarases from Persicobacter sp. DH-3 could be used to produce functional neoagarooligosaccharides.