• Fisheries and Aquatic Sciences
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• 제1권2호
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• pp.180-186
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• 1998

A 10-week feeding experiment was conducted to determine the phosphorus requirement of juvenile Korean rockfish (Sebastes schlegeli). Three replicate groups of fish initially averaging 4.2g were fed the semipurified experimental diets containing graded levels of $NaH_2PO_4\;\cdot\;2H_2O$ to provide from $0.1\%$ to $1.32\%$ total phosphorus level in a flow-through seawater system. Korean rockfish muscle and casein were used as the protein sources of the basal diet. Weight gain, feed efficiency and protein retention of fish fed the $0.35\%$ phosphorus were higher than those of fish fed the $0.1\%$ phosphorus, although no significant improvements $(P>0.01)$ were observed above the level. Determined phosphorus requirement using the broken line model was found to be $0.3\%$ for weight gain. Moisture, protein and lipid contents of whole body and muscle were not affected by dietary phosphorus levels $(P>0.01)$. Lipid contents of liver in fish fed the $0.1\%$ phosphorus were lower than those in fish fed the $0.35\%$ and $1.32\%$ phosphorus $(P<0.01)$. Dietary phosphorus increased ash and phosphorus contents of the whole body, while those of bone were not affected $(P>0.01)$. The data obtained in this study indicate that a $0.3\%$ dietaryphosphorus level could be recommended for the optimum growth and efficient nutrient utilization of juvenile Korean rockfish.

• 한국환경과학회지
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• 제15권8호
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• pp.745-757
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• 2006

We focus on the improvement of accuracy of sea surface wind over complex coastal area doling the warm season. Local Analysis Prediction System (LAPS) was used to improve the initial values in Mesoscale Meteorological model (MM5). During the clear summer days with weak wind speed, sea surface wind simulated with LAPS was compared with the case without LAPS. The results of modeling with LAPS has a good agreement mesoscale circulation such as mountain and valley winds on land and in case of modeling without LAPS, wind speed overestimated over the sea in the daytime. And the results of simulation with LAPS indicated similar wind speed values to observational data over the sea under influence of data assimilation using BUOY, QuikSCAT, and AMEBAS. The present study suggests that MM5 modelling with LAPS showed more improved results than that of without LAPS to simulate sea surface wind over the complex coastal area.

• 유기물자원화
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• 제22권2호
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• pp.17-26
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• 2014

본 연구에서는 벤토나이트를 이용하여 수용액상에서 혼합 중금속의 흡착 특성을 평가하였다. 벤토나이트는 SEM과 FT-IR에 의해 물리 화학적 성상을 분석하였고, 중금속 흡착 특성은 Freundlich 및 Langmuir 방정식을 이용하여 해석하였다. 평형흡착 실험결과는 Langmuir 모델에 잘 부합되었으며, $Pb^{2+}$ > $Cu^{2+}$ > $Cd^{2+}$ > $$Zn^{2+}{\sim_=}Ni^{2+}$$순으로 평형 흡착량이 높았다. 용액의 pH가 6에서 10으로 증가함에 따라 흡착량은 증가하는 경향을 나타내었다. SEM과 FT-IR에 의한 벤토나이트의 표면 관찰결과에서 주 관능기는 Si-O 및 Si-O-Al 로 나타났다. 이러한 결과로부터 중금속 흡착 메카니즘은 표면흡착과 이온교환뿐만 아니라 표면 침전이다. 본 연구 결과를 통해 벤토나이트는 수용액 내 중금속을 효율적으로 제거할 수 있는 흡착제로 판단된다.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2002년도 추계학술대회 논문집
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• pp.343-343
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• 2002

This study examines the influence of long-range transport of dust particles and air pollutants on both local/regional DMS oxidation chemistry and the distribution of sulfur compounds at Jeju Island (33.17$^{\circ}$ N. 126.10$^{\circ}$ E) during the Asian dust-storm(ADS) period in April 2001. The atmospheric concentrations of these sulfur species were measured at a ground station on Jeju Island. Korea as Part of the ACE-Asia intensive operation. Three ADS events were observed during the periods of 10-12, 13-14. and 25-26 April. respectively. The concentrations of DMS and CS$_2$ were higher during the ADS period than during the non-Asian-dust-storm (NADS) period. Conversely. a difference in SO$_2$ levels during the ADS period was not distinguishable from those during the NADS period. The diurnal variation pattern of DMS observed was largely different from that in the remote marine boundary layer. DMS loss by NO$_3$ in the atmospheric boundary layer was dominant due to significantly high NOx levels influenced by the long-range transport of pollutants from East Asia to Jeju Island The DMS maximum during the ADS period was observed in the late afternoon. The oceanic fluxes of DMS during the ADS and NADS periods were estimated to be 5.7$\pm$2.3 and 2.9 (+2.8/-1.5) mole m$^{-2}$ day$^{-1}$ . respectively. The contribution of oxidized DMS to SO$_2$ levels at Jeju Island during the study period was found to be insignificant.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.169-174
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• 1999

The reclamation area of Saemangeum (Kunsan) located between 126$^{\circ}$10' -126$^{\circ}$50'E and and 35$^{\circ}$35'N -36$^{\circ}$05'N at the western coast of Korea. The construction of the 33km sea dike is building in the Saemangeum area. When the construction of the sea dike in the coastal region takes plase, there exists a certain amount of soil which is diffused by the tidal current. Behavior of the soil diffusion usually depends on its intrinsic characteristics, bathymetry, construction method and used mchinery. The amount of soil at the construction acts as a pollutant which is the cause of changing the marine environment. When the soil material is diffused , it may form a layer which obstructs the light passing into the sea and causes the extinction or alteration of the living beings on the sea bottom. The settlement of soil material could change the sea bottom deposit. The purpose of MITIGATION is to harmonize the development and the conservation of environment, to restrict environmental destruction and to reproduce the enviroment damaged by the construction in the coastal region. The purpose of this study is to find the method by which we minimize the anti-function of development in the coastal region. Tide and tidal current are calculated using a two-dimensional numerical model before the construction of sea dike in Saemangeum Bay. The numerical results are compared well with field observations. On the basis of these results, we caculated the tide and tidal current after the construction of the sea dike in order to investigate the change of the tide and tidal current after the construction of the sea dike. Moreover, we calculated the tide and tidal current after the construction of submerged breakwater in order to preserve the enviornmental condition of creature habitat . We compared the tide and tidal current before and after the construction of submerbed breakwater, to investigate the possbility of MITIGATION in the fisheries.

• 한국수산과학회지
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• 제35권4호
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• pp.380-385
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• 2002

본 연구에 사용되어진 마루자주새우 (Crangon hakodatei)는 거제도 주변 해역에서 2000년 10월부터 2001년 10월까지 새우조망을 이용하여 매월 채집하였다. 이들 개체군의 구조, 성장, 사망 및 성 성숙에 관한 분석은 갑각장을 이용한 체장빈도 데이터를 이용 ELEFAN 프로그램에 의해 분석하였다. 성장계수의 추정은 변형된 von Bertalanffy 성장식을 이용하였다. 암컷이 수컷보다 성장이 빨라 성숙개체에 빨리 도달하는 것으로 나타났다. 체장변환 어획 곡선에 의해 구해진 전 사망계수는 $3.10yr^{-1}$로 나타났고, Pauly 식에 의해 산출된 자연사망계수는 $2.48yr^{-1}$로 나타났다. 또한 어획사망계수는 $0.62yr^{-1}$인 것으로 나타났다. 암컷의 성 성숙 개체의 크기는 갑각장 $11.00\~11.50$ mm 사이인 것으로 나타났다.

• 한국지능시스템학회논문지
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• 제24권5호
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• pp.512-517
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• 2014

본 연구는 선박의 외벽 유지보수를 위한 외벽 연마장비에 장착되는 먼지 집진장치에 적용하기 위한 사이클론 집진방식의 연마기 제작을 위한 사이클론 분리기 설계를 위하여 최적의 설계조건을 도출하고자 유동해석 기법을 적용한 사이클론 연마장비의 집진장치를 소개하고자 한다. 제작된 연마장비의 집진을 위한 접선유입 사이클론의 압력 강하와 입자 수집 능률은 기 연구된 수학적 모델을 적용하여 계산하였다. 종래 공기필터를 가진 사이클론의 계산 결과의 비교는 접선 유입 사이클론이 저압 드롭과 높은 입자 수집능률을 시뮬레이션을 통한 검증과 시작품을 제시하였다. 사이클론은 원통형 장치 내에 분진을 함유하는 기체를 장치내벽에 접선방향으로 유입시켜 유입분진에 선회운동을 부여함으로써 분진입자에 작용하는 원심력에 의하여 가스중의 입자를 분리 포집하는 집진장치로써 연마장비의 집진장치로 응용하고자 본 연구를 진행하여 진행중인 메커니즘과 유체흐름에 대한 기본적인 유체흐름에 따른 사이클론의 규격 파라미터에 따른 유동해석 결과를 제시하였다.

• 수산경영론집
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• 제46권3호
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• pp.83-101
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• 2015

The main purpose of this study is to explore a way of South-North Korea fisheries cooperation through international organizations under the principles of the Korean peninsula trust process. Considering the government policy toward the North, although some humanitarian aids or cooperations may be plausible with permission of the Ministry of Reunification. direct cooperations between the South and the North Korea must be much limited at leat under the present government. The 5.24 measures taken in 2010 banned in fact all economic/humanitarian cooperations by private sectors and government. Noting the present and the visible future, an important question is whether the North accepts all cooperations including fisheries, bartering giving up nuclear weapon development for the 5.24 measures. It would be a difficult question to be answered, because win-set to both parties is too narrow, so far as there is no change in the South-North conflicting priority policies. If so, one way of implementing South-North fisheries cooperations is to drive forward cooperative programs through UN organizations. Since for instance FAO and WFP secure justification and roles and has a global network, they have sufficient capacity of being abe to organize fisheries experts. If the South can finance the budget necessary for the programs, FAO or WFP would lead the programs through a negotiation with the North. In other words, it is a type of cooperative model that FAO or WFP leads the programs and the South finances. In addition, if World Fisheries University(WFU) is invited to the Republic of Korea, it might make a great contribution to expert exchange of the North.

• 한국항해항만학회지
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• 제28권8호
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• pp.687-697
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• 2004

본 논문의 목적은 외항선사들의 정치적 노출정도를 측정하는 정치적 비용과 이와 관련이 있는 재무적 요인들 간의 관련성 유무를 다변량 회귀분석방법에 의하여 실증 분석함으로써 우리나라 해운산업의 정치적 비용 결정요인을 검증하는 데 있다. 회귀모형의 독립변수는 기업규모(매출액, 총자산, 시장점유율) 외에 해운산업의 특성을 보여주는 부채비율, 자본집약도, 영업이익률 및 해운위험으로서 매출액변동이다. 분석 결과 해운기업의 정치적 비용과 모든 규모변수는 유의적으로 정의 관련성이 있는 것으로 나타나고 있다. 또한 부채비율과 영업이익률은 해운산업의 정치적 비용을 결정하는 주요 요인으로 밝혀졌다.

• 한국항해항만학회지
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• 제42권2호
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• pp.127-136
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• 2018

The motion response of floating structures is of significant concern in marine engineering. Floating structures can be disturbed by waves, winds, and currents that create undesirable motions of the vessel, therefore causing challenges to its operation. For a floating structure, mooring lines are provided in order to maintain its position; these should also produce a restoring force when the vessel is displaced. Therefore, it is important to investigate the tension of mooring lines and the motion responses of a twin barge when moored to guarantee the safety of the barge during its operation. It is essential to precisely identify the characteristics of the motion responses of a moored barge under different loading conditions. In this study, the motion responses of a moored twin barge were measured in regular waves of seven different wave directions. The experiment was performed with regular waves with different wavelengths and wave directions in order to estimate the twin-barge motions and the tension of the mooring line. In addition, the motion components of roll, pitch, and heave are completely free. In contrast, the surge, sway, and yaw components are fixed. In the succeeding step, a time-domain analysis is carried out in order to obtain the responses of the structure when moored. As a result, the Response Amplitude Operator (RAO) motion value was estimated for different wave directions. The results of the experiment show that the motion components of the twin barge have a significant effect on the tension of the mooring lines.