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The fishery and fishing ground environment for red horsehead (Branchiostegus japonicus) on the adjacent seas of Jeju Island (제주도 근해의 옥돔 어업과 어장 환경에 관한 연구)

  • Kim, Jeong-Chang;Kang, Il-Kwon;Kim, Dong-Sun;Lee, Jun-Ho
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.42 no.1
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    • pp.19-29
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    • 2006
  • To investigate the fishery and fishing ground environment of red horsehead (Branchiostegus japonicus), the author analyzed the fishery data and examined the amount of catches and oceanic environment on the adjacent seas of Jeju island and East China Sea. It was turned out that the favourable season of the red horsehead fishery is the month from March to June, the main fishing ground is located in 60 mile radius from the position $32.5^{\circ}N,\;125.7^{\circ}E$. The bottom seawater temperature in fishing ground was shown between $l3^{\circ}C\;and\;16^{\circ}C$, the salinity was appeared between 33.5 and 34.0psu without the seasonal variation of the year. Concentrations of materials(e.g, $NO_3^-\;and\;NO_2^-$) in spring and summer time in main fishing ground were higher than any other seasons, but that of phospheric materials were lower than any other seasons. Concentrations of $chlorophyll\;-\;{\alpha}$ in the main fishing ground was the highest in spring and summer at the surface layer, but the vertical profile of the $chlorophyll\;-\;{\alpha}$ concentrations in all seasons were not variable at bottom layer. Mean density of zooplankton abundance according to the vertical structure was higher and much stable in summer and autumn than spring and winter.

Effects of an Artificial Breakwater on the Distributions of Planktonic Microbial Communities

  • Kim, Young-Ok;Yang, Eun-Jin;Kang, Jung-Hoon;Shin, Kyoung-Soon;Chang, Man;Myung, Cheol-Soo
    • Ocean Science Journal
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    • v.42 no.1
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    • pp.9-17
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    • 2007
  • The summer distributions of planktonic microbial communities (heterotrophic and phtosynthetic bacteria, phtosynthetic and heterotrophic nanoflagellates, ciliate plankton, and microphytoplankton) were compared between inner and outer areas of Lake Sihwa, divided by an artificial breakwater, located on the western coast of Korea, in September 2003. The semi-enclosed, inner area was characterized by hyposaline surface water (<17 psu), and by low concentrations of dissolved oxygen (avg. $0.4\;mg\;L^{-1}$) and high concentrations of inorganic nutrients (nitrogenous nutrients $>36\;{\mu}M$, phosphate $>4\;{\mu}M$) in the bottom layer. Higher densities of heterotrophic bacteria and nanoflagellates also occurred in the inner area than did in the outer area, while microphytoplankton (mainly diatoms) occurred abundantly in the outer area. A tiny tintinnid ciliate, Tintinnopsis nana, bloomed into more than $10^6\;cells\;L^{-1}$ at the surface layer of the inner area, while its abundance was much lower ($10^3-10^4\;cells\;L^{-1}$) in the outer area of the breakwater. Ciliate abundance was highly correlated with heterotrophic bacteria (r = 0.886, p < 0.001) and heterotrophic flagellates (r = 0.962, p < 0.001), indicating that rich food availability may have led to the T. nana bloom. These results suggest that the breakwater causes the eutrophic environment in artificial lakes with limited flushing of enriched water and develops into abundant bacteria, nanoflagellates, and ciliates.

The numerical simulation on variation of phytoplankton maximum region in the estuary of Nakdong river -II. The numerical simulation on variation of phytoplankton maximum region- (낙동강 하구지역의 식물플랑크톤 극대역 변동에 관한 수직시뮬레이션 -II. 식물플랑크톤 극대역 변동의 수치시뮬레이션-)

  • 이대인
    • Journal of Environmental Science International
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    • v.9 no.5
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    • pp.375-384
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    • 2000
  • It is very important to interprete and simulate the variation of phytoplankton maximum region for the prediction and control of red tide. This study was composed of two parts first the hydrodynamic simulation such as residual current and salinity diffusion and second the ecological simulation such as phytoplankton distribution according to freshwater discharge and pollutant loads. Without the Nakdong river discharge residual current was stagnated in inner side of this estuary and surface distribution of salinity was over 25psu. On the contrary with summer mean discharge freshwater stretched very far outward and some waters flowed into Chinhae Bay through the Kadok channel and low salinity extended over coastal sea and salinity front occurred. From the result of contributed physical process to phytioplankton biomass the accumulation was occurred at the west part of this estuary and the Kadok channel with the Nakdong river discharge. When more increased input discharge the accumulation band was transported to outer side of this estuary. The frequently outbreak of red tide in this area is caused by accumulation of physical processes. The phytoplankton maximum region located inner side of this estuary without the Nakdong river discharge and with mean discharge of winter but it was moved to outer side when mean discharge of the Nakdong river was increased. The variation of input concentration from the land loads was not largely influenced on phytoplankton biomass and location of maximum region. When discharge was increased phytoplankton maximum region was transferred to inner side of the Kadok channel. ON the other hand when discharge was decreased phytoplankton maximum region was transferred to inner side of this estuary and chlorophyll a contents increased to over 20$\mu\textrm{g}$/L Therefore if any other conditions are favorable for growth of phytoplankton. decreas of discharge causes to increase of possibility of red tide outbreak.

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The Air Quality Modeling According to the Emission Scenarios on Complex Area (복잡지형에서의 배출량 시나리오에 따른 대기질 수치모의)

  • Lee, Hwa-Woon;Choi, Hyun-Jung;Lee, Soon-Hwan;Lim, Heon-Ho;Lee, Kang-Yoel;Sung, Kyoung-Hee;Jung, Woo-Sik;Park, Jeong-Im;Moon, Nan-Kyung
    • Journal of Environmental Science International
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    • v.16 no.8
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    • pp.921-928
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    • 2007
  • The objective of this work is the air quality modeling according to the scenarios of emission on complex terrain. The prognostic meteorological fields and air quality field over complex areas of Seoul, Korea are generated by the PSU/NCAR mesoscale model (MM5) and the Third Generation Community Multi-scale Air Quality Modeling System (Models - 3/CMAQ), respectively. The emission source was driven from the Clean Air Policy Support System of the Korea National institute of Environmental Research (CAPSS), which is a 1 km x 1 km grid in South Korea during 2003. In comparison of air quality fields, the simulated averaged $PM_{10},\;NO_2,\;and\;O_3$ concentration on complex terrain in control case were decreased as compared with base case. Particularly $PM_{10}$ revealed most substantial localized differences by $(18{\sim}24{\mu}g/m^3)$. The reduction rate of $PM_{10},\;NO_2,\;and\;O_3$ is respectively 18.88, 13.34 and 4.17%.

Sensitivity Analysis of Simulated Precipitation System to the KEOP-2004 Intensive Observation Data (KEOP-2004 집중관측 자료에 대한 강수예측의 민감도 분석)

  • Park, Young-Youn;Park, Chang-Geun;Choi, Young-Jean;Cho, Chun-Ho
    • Atmosphere
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    • v.17 no.4
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    • pp.435-453
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    • 2007
  • KEOP (Korea Enhanced Observing Period)-2004 intensive summer observation was carried out from 20 June to 5 July 2004 over the Southwestern part of the Korean peninsula. In this study, the effects of KEOP-2004 intensive observation data on the simulation of precipitation system are investigated using KLAPS (Korea Local Analysis and Prediction System) and PSU/NCAR MM5. Three precipitation cases during the intensive observation are selected for detailed analysis. In addition to the control experiments using the traditional data for its initial and boundary conditions, two sensitivity experiments using KEOP data with and without Jindo radar are performed. Although it is hard to find a clear and consistent improvement in the verification score (threat score), it is found that the KEOP data play a role in improving the position and intensity of the simulated precipitation system. The experiments started at 00 and 12 UTC show more positive effect than those of 06 and 18 UTC. The effect of Jindo radar is dependent on the case. It plays a significant role in the heavy rain cases related to a mesoscale low over Changma front and the landing of a Typhoon. KEOP data produce more strong difference in the 06/18 UTC experiments than in 00/12 UTC, but give more positive effects in 00/12 UTC experiments. One of the possible explanations for this is that : KEOP data could properly correct the atmosphere around them when there are certain amounts of data, while gives excessive effect to the atmospheric field when there are few data. CRA analysis supports this reasoning. According to the CRA (Contiguous Rain Area) analysis, KEOP data in 00/12 UTC experiments improve only the surrounding area, resulting in essentially same precipitation system so the effects remain only in each convective cell rather than the system itself. On the other hand, KEOP data modify the precipitation system itself in 06/18 UTC experiments. Therefore the effects become amplified with time integration.

A Case Study on the Formation of Contract under the CISG (CISG상 계약의 성립에 관한 판례연구)

  • LEE, Byung-Mun;PARK, Eun-Ok
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.69
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    • pp.1-22
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    • 2016
  • This study primarily concerns the cases recently held as to the formation of contract under the CISG. In order to put forward the most plausible direction to interpret the rules on the formation of contract under the CISG, it particularly deals with the followings. First, it scrutinizes the rules on the formation of contract, focusing on the requirements of offer and acceptance, the time when such offer and acceptance become effective, the issues on the battle of forms. Second, it introduces two recent interesting cases regarding the formation of contract and provides legal and practical advice to the contracting parties when they intend to conclude a contract under the CISG as a governing law. The followings are practical points that the parties should consider when they enter into contract. First, as any signature or intial made in the offer could be regarded as an acceptance, the parties are required to clarify the meaning of such signature or initials before the conclusion of contract. Second, it is not necessarily required one's signature for an offer to become effective but his name. Third, standard terms cannot be incorporated into the contract simply by reference to web-page or other documents. In order for such terms to be incorporated, it may be necessary to enclose them in the offer or to bring the other party's attention to them. Forth, one should remember that an acceptance by act become effective not when such act is complete, but when it is performed.

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Influence of Sargassum beds on the Water Quality Characteristics in Gamak Bay, Korea (가막만의 모자반군락이 수질환경에 미치는 영향)

  • An, Yun-Keun;Cho, Ju-Hyon;Yoon, Ho-Seop;Park, Il-Woong;Kim, Yun-Seol;Kim, Ho-Jin;Choi, Sang-Duk
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.42 no.3
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    • pp.284-289
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    • 2009
  • We determined the influence of Sargassum beds on the water quality in Gamak Bay, Korea. Water temperature and salinity range from 3.3 to $23.4^{\circ}C$ and from 29.6 to 33.7 psu, respectively. Dissolved oxygen was 10.45 mg L-1 in the Sargassum bed and 9.23 mg L-1 in the control. Chlorophyll-a was $3.90{\mu}g\;L^{-1}$ in the Sargassum bed and 2.21${\mu}g \;L^{-1}$ in the control. Chemical oxygen demand were 1.14${\mu}g\;L^{-1}$ in the Sargassum bed and 1.43${\mu}g\;L^{-1}$ in the control. Total nitrogen were 0.038${\mu}g\;L^{-1}$ in the Sargassum bed and 0.067${\mu}g \;L^{-1}$ in the control. Total phosphorus were 0.043${\mu}g \;L^{-1}$ in the Sargassum bed and 0.072${\mu}g \;L^{-1}$ in the control. Multivariate statistical analysis was used to analyze data. Water temperature was highly positively correlated with DO (p<0.01). T-N was highly positively correlated with T-P (p<0.01).

Species Composition and Monthly Variation of the Organisms attached to Sargassum beds in Gamak Bay, Korea (가막만 모자반군락지내 부착생물의 종조성 및 월별변동)

  • Kim, Yun-Seol;Yoon, Ho-Seop;Park, Il-Woong;An, Yun-Keun;Choi, Sang-Duk
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.43 no.4
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    • pp.345-350
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    • 2010
  • We studied the organisms attached to Sargassum beds in Gamak Bay from November 2007 to June 2008. The water temperature ranged from 3.3 to $28.7^{\circ}C$ and salinity from 30.6 to 33.8 psu. Eighteen species $143,432\;ind./m^2$ were sampled during study periods. The biomass of the Sargassum beds ranged from a highest of $196.08\;g\;dw/m^2$ in March to a lowest of $0\;g\;dw/m^2$ in July. The major dominant species were Barleeia angustata ($134,430\;ind./m^2$), Caprellidae sp.($2,443\;ind./m^2$) and Gammaridae sp.($4,201\;ind./m^2$). The ecological indices of diversity, evenness, and richness were 0.11-0.86, 0.04-0.39, and 0.74-1.06, respectively.

The Oceanic Condition of the Tsushima Warm Current Region in the Southern Part of the East Sea (Sea of Japan) in June, 1996.

  • Lee, Chung-Il;Cho, Kyu-Dae;Yun, Jong-Hwui
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.9 no.2
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    • pp.65-72
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    • 2003
  • Oceanic conditions of the Tsushima Warm Current (TWC) region in the southern area of the East Sea (Japan Sea) are examined using data obtained from a CREAMS (Circulation Research if the East Asian Marginal Seas) cruise in June 1996. In 1990s, a lower temperature appears in 1996 and in this period, two branches of the TWC exist and the first branch of the TWC flows inshore of the Japanese coastal region compared to that in the other years, especially in the shallower water layer at depth less than about 200 m. The TWC cored with the higher salinity (>34.6 psu) is clearly observed over the continental shelf in the Japanese coastal region and offshore and identified by geostrophic calculation. Intrusion of the TWC into the East Sea through the Korea Strait (the Tsushima Strait) makes the density structure in the water column change and the water mass in the TWC region is unstable based on Brunt­Vaisala frequency.

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Uptake and Loss Kinetics of Silver in the Asian Clam, Potamocorbula amurensis and Balthic Clam, Macoma balthica: Effects of Body Size and Salinity (Potamocorbula amurensis와 Macoma balthica의 개체의 크기와 염분이 은의 흡수 및 배출에 미치는 영향)

  • Choi, Tae-Seob;Lee, Jung-Suk;Lee, Byeong-Gweon;Kim, Kwang-Young
    • The Korean Journal of Malacology
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    • v.21 no.1
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    • pp.47-56
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    • 2005
  • A series of radiotracer experiments were employed to quantitatively compare the biokinetics of uptake from the dissolved phase (influx rates), uptake from the various types of food source (assimilation efficiency), and loss (efflux) of Ag between Potamocorbula amurensis and Macoma balthica. Simultaneously, influx rates of dissolved Cd in both clams were determined to compare with those of Ag. Effects of salinity on influx rates were evaluated in these 2 euryhaline species, as were effects of clam size. Influx rate of Ag and Cd (${\mu}g g^{-1}$ [dry wt.] $d^{-1}$) increased linearly with metal concentrations. Influx rates of Ag in both clams were 3 to 4 times those of Cd. Absolute influx rates of the 2 metals were 4 to 5 times greater in P. amurensis than M. balthica, probably because of differences in biological attributes (i.e. clearance rate or gill surface area). As salinity was reduced from 20 to 2.5 psu, the influx rate of Cd in P. amurensis increased 4-fold and that of Ag increased 6-fold, consistent with expected changes in speciation. Weight-specific metal influx rates (${\mu}g g^{-1}$ [dry wt.] $d^{-1}$) were negatively correlated with the tissue dry weight of the clams, but most rate constants determining physiological turnover of assimilated metals were not affected by clam size.

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