• Journal of Environmental Impact Assessment
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• v.13 no.5
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• pp.231-241
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• 2004

This study aims to detect the change of marine aquaculture farm within the boundary of Hallyeo Marine National Park. Comparison has been made on the Landsat images taken in 1984 and 2002 respectively by using feature extraction methods and other image analysis techniques. During the 18 year period between 1984 and 2002, total area of the aquaculture farms has been decreased in 63 percent. The reason for the change seems to be that aquaculture farms became concentrated only around the Geoje Islands due to the growth of the labor- and capital-intensive cage aquaculture for the expensive fish species instead of traditional oyster farming. Authors suggest the monitoring using remotely-sensed data as the best tool for the management of marine aquaculture farms on the basis of accuracy of analysis and relatively cheap cost. Management strategies of salmon farms in Tasmania, Australia has been analyzed to find the field techniques necessary for the management of aquaculture.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.4
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• pp.390-400
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• 2021

One of the problems with abalone farms is that they need to be checked frequently after feeding them or visited once or twice a day and that the amount of food intake constantly fluctuates due to changes in water temperature around the farm and typhoons. In addition, the condition of abalone is not constant as it is divided into places that eat well and do not eat well according to its location. In order to solve this problem, there is a method of measuring the amount of food intake by using a load cell that can measure even the smallest weight in an abalone farm. Through this study, we implemented a system capable of measuring the amount of abalone feed required for systematic management of abalone farms and real-time monitoring using mobile and client PCs.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.59 no.2
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• pp.181-187
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• 2023

Laver aquaculture, which occupies a large proportion in the aquaculture industry in Korea, is still highly dependent on human labor. Therefore, it is necessary to study the development of an automatic system to improve the working environment and increase the efficiency of aquaculture production systems. The purpose of this study is to evaluate the economic feasibility of an improved system in a study for the loading-unloading and automatic weighing systems in laver aquaculture industry. Economic analysis of the developed unloading and automatic weighing system were implemented under various conditions to calculate more accurate benefits and costs. As a result of this study, the economic feasibility was found to be very high in the three models: net present value (NPV), benefit-cost ratio (B/C), internal rate of return (IRR). Moreover, the results of sensitivity analysis showed that the economical efficiency of the automatic loading, unloading, and weighing system in laver aquaculture was very high.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.4
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• pp.158-165
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• 2010

Phytoplankton community structure is one of the indicators that can explain the enviromnental characteristics of coastal waters. In this study, phytoplankton community structure and water quality of aquaculture area were investigated for understanding regional enviromnental characteristics. Thirty stations in aquaculture areas of Tongyeong, southeast coast of Korea, were investigated monthly from January to December, 2009. Phytoplankton community, meteorologic dada and enviromnent factors including temperature, salinity, transparency, nutrients and chlorophyll a were also examined. Chaetoceros spp. and unidentified small flagellates were dominant species in all the year round. Pseudo-nitzschia spp., Dictyocha spp., and Nitzschia longissima were dominant in June to October being summer season, and Skeletonema costatum, Thalassiosira spp., Eucamphia zodiacus, Akashiwo sanguinea, Gymnodinium spp. and Asterionella japonicus appeared as dominant species in the rest of months. Dinoflagellate blooms occurred 3 times in near Hansan Bay and around Saryang-do, and the highest chlorophyll a was found in Hansan Bay. Species diversity of phytoplankton was lower in Hansan and Womnum Bay, and diatom was more abundant than dinoflagellates in Mireuk-do waters. These results showed that phytoplankton community varied by the seasonal and geographical characteristics, and recent increase of water temperature and heavy rain may affect on phytoplankton community structure.

• Journal of Aquaculture
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• v.7 no.4
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• pp.239-249
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• 1994

This study was conducted to elucidate mixing characteristics of the media to dertermine hydraulic model parameters of the three phase fluidized bed for the water quality management of aquaculture. The volume and H/D ratio of the reactor were 1.76 Liter and 10.9, respectively. The experimental results showed that variance $(\sigma^2)$ and dispersion number $(D/{\mu}L)$ were above 0.47 and $0.35\~\infty$, respectively. Therefore, the condition of the reactor was almost ideal complete mixing. The dependence of the overall oxygen-transfer coefficient $(K_{La})$ on each experimental variables through a multple linear regression was given by the following equation ; $$K_{La}\;=\;44.9(D_i/D_c)^{-0.4611}\;A_f^{0.8622}\;C_m^{-0.0746}\;d_p^{-0.4302}$$

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.215-215
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• 2011

1996년도 UN해양법협약의 발효와 각국의 배타적 경제수역(EEZ) 선포로 연안역에 대한 관심이 국제적으로 고조되고 있는 가운데 우리나라에서도 연안역 관리법(가칭)이 제정되었다. 국토해양부는 연안역 공간이용 효율성 극대화와 부존 해양자원의 치계적인 개발과 보전을 위하여 연안역 관리법을 특별법으로 제정하였으며 1998년 중에 시행령 등 하위법령을 제정해 시행키로 하였다. 이 이후로도 연안역 특별법에 대한 연구는 계속 진행중이며, 현제 연안역은 연안어업, 수산양식장, 모래채취, 염전, 해수욕장, 관광지, 해양시설, 간척, 매립지, 공업단지 등으로 많이 이용되고 있다. 그러나 연안역 안전시설에 대한 상세 설계기준 및 시공에 대해서는 자세히 다루고 있지 않다. 연안역은 관광객이 증가하면서 안전시설과 구난장비의 미비한 실정으로 인해 인적 물적 피해가 빈번히 발생 증가하고 있는 것으로 나타나고 있다. 안전사고의 다발지역을 분석해 보면 관광객으로 인하여 방파제 주변에서의 안전사고가 증가하고 있는 상황이며, 이로 인한 인명피해도 증가하고 있다. 방파제에 대한 안전사고를 막기 위하여 우선적으로 방파제에 대한 안전사고를 해결하고자 인명피해를 막는 구난시설들에 대한 간격 등의 기준을 제시하였다. 다른 지역에 비하여 연안역은 파도에 의하여 사람이 떠내려가는 것을 고려하여 구난시설의 간격을 해안이나 다른 안전시설에 비하여 더 짧게 하였으며, 구난시설이 피해자에게 빠르게 전달되고자 멀리 던진 수 있으며, 구난시설을 잡음과 동시에 숨을 쉴 수 있는 여건이 조성되도록 연구하였다. 안전사고를 효율적으로 방지하기 위하여 인간공학을 접한 안전시설을 연구를 하였다. 인간공학이란, 인간의 행동, 능력, 한계, 특성 등에 관한 정보를 발견하고, 이를 도구, 기계, 시스템, 과업, 직무, 환경의 설계에 응용함으로 인간이 생산적이고 안전하며 쾌적하고 효과적으로 이용할 수 있도록 하는 것이다. 인간공학은 인간이 사용할 수 있도록 설계하는 과정에 있어 인간의 활용성 및 편리성을 증대하는 학문으로 보며, 설계초기 단계에서부터 인간의 요소의 체계적인 고려를 필요로 하게 되었다. 이 논문은 과거에 일어났던 사고사례들을 주시하면서 앞으로의 미래에 똑같은 사고사례가 발생하지 않도록 예방하이 위하여 인간공학과 안전시설을 통하여 연안역의 안전시설의 설치기준에 도움이 되는 자료를 제공하고자 한다.

• The Korean Journal of Malacology
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• v.23 no.1
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• pp.25-30
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• 2007

In order to estimate the ecological parameters of the population, short-necked clams, Ruditapes philippinarum, were collected from Jindu coast at Hansan Island, from April to December in 2005. The growth of the clam was estimated by von Bertalanffy growth model and each parameters were obtained from a nonlinear regression as $L_{\infty}\;=\;48.8\;mm$, k = 0.28 and $t_0\;=\;-0.88\;(R^2\;=\;0.994)$. Instantaneous coefficient of total mortality (Z) and fishing mortality (F) was calculated to be 0.8614/yr. and 0.6122/yr, respectively. The age at the first capture was estimated to be 2.88 year. Using the present parameter for clam fishing, the yield-per recruit (Y/R) was estimated to be 3.44g. Although the maximum Y/R was obtained under the parameters ($t_c\;=\;3.48\;yr$. and F = 0.9295/yr), it is favorable to maintain the current fishing effort considering the annual fluctuation of the parameters.

• Journal of fish pathology
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• v.32 no.1
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• pp.29-35
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• 2019

A monitoring was performed to survey the mortalities that had occurred in the aquaculture farms of olive flounder (Paralichthys olivaceus) in South Korea from 2015 to 2017. The indirect inquiry for entire farms and the sample survey for selected farms were carried out. The aquatic organism disease inspectors, who have a national license for the diagnosis and prevention of aquatic organism diseases and a have close relationship with the farms, investigated the rates and causes of mortalities according to the standard manual. The mortality rate by sample survey of farms in 2015, 2016, and 2017 were 24.78% (Chunnam: 17.86%, Jeju: 28.69), 30.19% (Chunnam: 24.45%, Jeju: 32.65), and 21.59% (Chunnam: 10.57%, Jeju: 26.00%), respectively. The major cause of mortality was scuticociliatosis, and the mortality caused by viral hemorrhagic septicemia and emaciation disease (Jeju) were also high. Our results can contribute to effective establishment prevention of epidemics system and acquired status as a disease-cleansing country.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.5
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• pp.179-186
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• 2021

We need measures that can come up with alternative about fishery living zone and enhance local acceptance for responding to the increase in the proportion of renewable energy production and construction of 12GW Offshore wind power according to Korea's Renewable Energy 3020 initiative and Korean-version New Deal. In this study, We suggest that differentiation plans of co-location model in connection with offshore wind power generation suitable for the East Sea. The East Sea is an optimal site for building of a floating offshore wind power generation(FOWPG) field. It is expected that economic effects like energy production, aquatic resource development and tourism industrialization by farming bluefin tuna which is high valued fish and suitable for offshore aquaculture on public waters in FOWPG field. And we can confirm that budget reduction, smart management by sharing operation management technology and increase in fishermen income.

• Journal of the Korean association of regional geographers
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• v.7 no.2
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• pp.82-96
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• 2001

The purpose of this study is to investigate the wise use and the management of intertidal environment. For tills purpose, we selected the Kanghwa island mudflat which is one of the most important intertidal region in Korea peninsula. The main research method is surface sediment and several map analysis. The results are as follows. (1) The study area is worldwide coastal wetland in view of ecology and geomorphology. But most of the salt marsh has been reclaimed since Japanese colonial period, the study area is mainly composed of mudflat. (2) The mean tidal regime of study area is 7.3m. From this tidal regime, the study area is subdivided into four distinct areas: the high intertidal area the middle intertidal area the low intertidal area and the shallow sea area terrestrial area near mudflat. (3) The mean particle size of surface sediment is sand 41.5%, silt 47.3%, clay 11.2%. This particle size pattern indicates the ecological characteristics of surface sediment of the study area. The proportion of clay is increasing to the open sea. (5) The pursuit of the wise use and the management must be implemented by the consideration of not only ecologic and sedimentary characteristics but also of the eco-tour site plan. And the entire use and management subject is different in each area.