• Journal of the korean society of oceanography
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• 제39권1호
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• pp.35-45
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• 2004

Based on the MASNUM wave-current coupled model, the temperature and salinity structures along $36^{\circ}N$ in the Yellow Sea are simulated and compared with observations. Both the position and strength of the simulated thermocline are similar to data analysis. The wave-induced mixing is strongest in winter and plays a key role in the formation of the upper mixed layer in spring and summer. Numerical experiments suggest that in the coastal area, wave-induced mixing and tidal mixing control the vertical structure of temperature and salinity.

• Journal of Plant Biology
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• 제33권2호
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• pp.141-146
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• 1990

Germination and vegetative growth of Enteromorpha multiramosa Bliding from Pyoson, Cheju Island were investigated in laboratory under various combinations of temperature (5-$25^{\circ}C$) and salinity (8-48$^{\circ}C$). Percent level of germination was relatively high at all combinations of the two factors. The highest value among the combinations was revealed at 15$^{\circ}C$ and 32$\textperthousand$. Dry weight also was fairly high at all levels of combination with maximum value at 2$0^{\circ}C$ and 32$\textperthousand$. Analysis of variance for germination and growth was completed respectively and polynomial prediction models were constructed. F ratio revealed that all factors had a significant effect (p<0.001) on percentage of germination and dry weight, and their interactions also were significant (p<0.001), although the F ratio of interactions was far less than that for either the separate effect of temperature or salinity. Response surface of polynomial equation represented that temperature influenced less than salinity on germination, while it effected remarkably on vegetative growth, so the Enteromorpha multiramosa was kept to visible macrothalli from winter to spring in Cheju Island.

• 한국수산과학회지
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• 제36권6호
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• pp.632-640
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• 2003

Geographic variation in shell morphology of Thais clavigera $(K\"{u}ster)$ (Gastropoda: Muricidae) was investigated using samples collected from 24 sites along the Korean coast. Multivariate statistical analysis was applied to 9 morphometric and 4 categorical variables. The shells of T. clavigera were classified into two distinct morph types (Type-W and -E). Temperature and salinity of the sampling sites were significantly correlated with the incidence of morph types. Relative abundance of Type-W (thin, yellowish brown shell with triangular nodules) was positively correlated with temperature and negatively correlated with salinity. In contrast, relative abundance of Type-E (thick, dark purple shell with round nodules) was negatively correlated with temperature and positively correlated with salinity. Possible correlation between environmental factors (temperature and salinity) and morphological variations in the shells were discussed.

• 한국해양공학회지
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• 제29권6호
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• pp.418-426
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• 2015

Recently, shipping operators have been making efforts to reduce the fuel cost in various ways, such as trim optimization and bulb re-design. Furthermore, IMO restricts the hydro-dioxide emissions to the environment based on the EEDI (Energy Efficiency Design Index), EEOI (Energy Efficiency Operational Indicator), and SEEMP (Ship Energy Efficiency Management Plan). In particular, ship speed is one of the most important factors for calculating the EEDI, which is based on methods suggested by ITTC (International Towing Tank Conference) or ISO (International Standardization Organization). Many shipbuilding companies in Korea have carried out speed trials around the Korea Straits. However, the conditions for these speed trials have not been exactly the same as those for model tests. Therefore, a ship’s speed is corrected by measured environmental data such as the seawater temperature, density, wind, waves, swell, drift, and rudder angle to match the conditions of the model tests. In this study, fundamental research was performed to evaluate the ship resistance performance due to changes in the water temperature and salinity, comparing the ISO method and numerical simulation. A numerical simulation of a KCS (KRISO Container ship) with a free-surface was performed using the commercial software Star-CCM+ under three conditions that were assumed based on the water temperature and salinity data in the Korea Straits. In the simulation results, the resistance increased under low water temperature & high salinity conditions, and it decreased under high water temperature & low salinity conditions. In addition, the ISO method showed the same result as the simulation.

• 수산해양기술연구
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• 제33권2호
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• pp.132-140
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• 1997

The basic experiment on the telemetry system of temperature and salinity, which is a study for the effective management of costal fishing-ground nowadays, was carried of 8 days from April 5, 6, 26, 27 , 1996 to May 31 and June 1, 21, 22, 1996 at the fish farm of Yooksam at Samyang-Myun, tongyongkun(34。45.02'N, 128。24.79'E). The results obtained were as follows : 1. The average temperature and salinity of STD of telemetry system was coincided with that of ICTD system calibration precisely. 2. A daily variation of temperature in fish cage which was measured by the telemetry system was influenced mainly by sunrise and sunset. 3. A daily variation of salinity in fish cage which was measured by the telemetry system was influenced mainly by tidal current. 4. The fish school in fish cage was distributed mainly 2~7 m layer during daylight and was arisen to the surface at sunset, was settled down to the bottom at sunrise.

• 수산해양기술연구
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• 제34권2호
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• pp.159-164
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• 1998

In order to investigate the relation between the environmental factors influencing on the fluctuation of fishing condition and the catch of anchovy in gill nets in the coastal waters of Yosu, five oceanographic factors, i.e., water temperature, salinity, chlorophyll-a and the catch of anchovy in gill nets are observed from June 6 to August 12 in 1993. The results obtained are summerized as follows: 1) The water temperature ranged from 16.$0^{\circ}C$ to 22.6$^{\circ}C$ and the salinity from 30.13$\textperthousand$ to 33.65$\textperthousand$. the water temperature and salinity showed no significant influence on the catch of anchovy, but the catch did not expose high values in low temperature and salinity. 2) The catch of anchovy increased with the amount of chlorophyll-a. It is therefore emphasized that the amount of chlorophyll-a is the greatest one of environmental factors influencing on the catch of anchovy.

• 해양환경안전학회지
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• 제9권2호
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• pp.59-64
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• 2003

국립수산과학원에서 장기간 관측한 정선해양관측자료와 연안정지관측자료를 이용하여 한국주변해역의 수온과 염분의 장기변화경향과 수층별 상관성을 보고자 하였다. 장기변화의 분석결과 한국연안수온은 하계냉수역이 발생하는 한국남서연안을 제외하고 상승하는 것으로 나타났다. 근해수온은 동해의 경우 표층은 상승하는 경향을 보인 반면 50m 와 l00m 수층은 하강하는 경향을 보였다. 남해의 경우 전 수층에서 상승하는 것으로 나타났으며, 서해의 경우 표층에서는 상승하나 50m 수층은 하강하는 것으로 나타났다. 근해염분은 동해의 경우 표층에서 하강하는 경향을 보인 반면, 50m 수층에서는 상승하는 경향을 보였으며, 100ml 수층 하강정도가 미미하게 나타났다. 남해의 경우 표층에서는 하강하는 경향을 보였으며, 50m 와 l00m 수층에서는 상승하는 경향을 보였다. 서해의 경우 표층과 50m 수층 모두 하강하는 경향을 보였다. 수층별 상관성을 보면 수온의 경우 동해와 남해에서 50m 수층과 100m 수층이 높은 상관도를 보였으나 서해의 경우 표층과 50m 수층 사이에는 상관성이 없는 것으로 나타났다. 염분의 경우 동해에서는 표층과 50m 수층이, 남해에서는 50m 와 l00m 수층이, 서해에서는 표층과 50m 수층이 높은 상관도를 보였다.

• 한국해양학회지:바다
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• 제17권3호
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• pp.139-148
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• 2012

하구언이 설치된 하구의 여름철 환경변화는 방류되는 담수에 의해 결정된다. 본 연구에서는 영산강 하구언 담수방류에 의한 하구의 염분 및 수온 분포를 파악하기 위하여 2010년 6월 소규모 방류시와 8월의 집중방류 중 후로 3회에 걸쳐 8개 정점에서 관측한 CTD 자료를 분석하였다. 6월의 소규모 방류시 표층염분은 30~32.5 psu를 나타냈고, 수평구배는 고하도 근해에서 다른 해역에 비해 상대적인 큰 값을 보여주었다(0.25~0.32 psu/km). 그러나, 저층염분은 약 33 psu의 일정한 값을 보여 수평구배는 존재하지 않았다. 영산강 하구내 수온은 $19{\sim}21^{\circ}C$ 범위를 보이며 동서방향보다 남북방향의 구배가 상대적으로 크게 나타났다. 대규모 방류가 진행 중이었던 8월 12일의 경우 표층염분은 9~26 psu로 감소하였다. 또한, 고하도 북쪽 수로의 표층과 저층 수평구배가 각각 3.79 psu/km와 0.28 psu/km인 강한 염분전선이 형성되었다. 수온은 하구언에서 높고 멀어질수록 감소하는 경향을 보였으며, 고하도 북쪽수로 표층과 저층에서 각각 $-0.45^{\circ}C/km$와 $-0.12^{\circ}C/km$의 공간적 변화가 나타났다. 집중방류 후(3차 관측) 표층염분은 22~26 psu로 회복되었으나 고하도 주변해역에서 여전히 높은 수평구배가 나타났다. 저층염분은 26.5~27.5 psu의 범위로 전반적으로 감소하였으나 수평구배는 크지 않았다. 하구언 가까운 정점에서 관측한 염분과 수온 시계열 자료에 의하면, 상층의 고온저염수가 일시적으로 하강하였다가 빠르게 회복하는 패턴을 보여주었는데, $13{\times}10^6$ 톤 방류시 회복속도는 약 0.4 m/hr로 나타났다. 영산강 하구는 대규모 방류 후 전반적으로 저염화되고, 여름철의 강한 태양복사에 의해 표층수온은 증가하여 하구 내 성층구조가 강화되고 수직혼합이 억제되는 환경이 형성되었다. 담수방류에 따른 염분의 공간적인 분포특성을 볼 때, 수평구배가 높은 고하도 주변해역, 고하도에서 하구언까지 염분이 낮은 내측해역, 그리고 상대적으로 높은 염분을 보이는 고하도에서 연안까지 외측해역으로 구분할 수 있다.

• 한국수산과학회지
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• 제43권2호
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• pp.139-145
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• 2010

This study investigated the optimum salinity and temperature conditions for mass culture of the brackish water flea, Diaphanosoma celebensis. Community and individual cultures of flea were maintained in 1 L beakers and 3 mL vessels (of a 12-well culture plate), respectively, and fed green algae, Tetraselmis suecica. In salinity experiments ranging from 5 to 34 psu, continuous growth of flea populations was found up to 34 psu. However, the specific growth rate and life span of females showed decreasing tendencies with the increase of salinity. The highest maximum density and offspring number were 33.6 individuals (ind.)/mL and 55.3 ind. at 10 psu, respectively. In the temperature experiments ranging from 20 to $40^{\circ}C$, population growth of D. celebensis increased continuously until $35^{\circ}C$ and then decreased over $40^{\circ}C$. The specific growth rate was significantly higher at 25 and $30^{\circ}C$ than at 20 and $40^{\circ}C$. Female life span tended to decrease with temperature increase. The highest maximum density and offspring number were 52.3 ind./mL and 46.0 ind. at $30^{\circ}C$, respectively. These results suggest that the optimum salinity and temperature for mass culture of D. celebensis may be 10 psu and $30^{\circ}C$, respectively.

• 한국어류학회지
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• 제35권1호
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• pp.39-43
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• 2023

실험구의 수온은 13, 16, 19, 22, 25℃로 설정하였고, 염분농도는 각각 7, 14, 21, 28, 32 psu로 설정하였으며, 200 L 플라스틱 원형수조에 부화 자어를 각각 500마리씩 수용하였다. 성장은 수온 25℃(21.62±0.14 mm TL)와 염분 28 psu (15.02±0.05 mm TL)에서 가장 높았고, 수온 13℃ (7.04±0.05 mm TL)와 염분 7 psu에서 가장 낮았다. 생존율은 수온 22℃(69.2%)와 염분 32 psu (84.1%)에서 가장 높았으며, 수온 13℃(15.1%)와 염분 7 psu에서 가장 낮았다. 양태는 강어귀 또는 연안 해역에 서식하여 채집이 가능한 어종으로 다른 해수 어종에 비해 염분 내성이 강하였다.