• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.671-676
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• 2011

To determine the optimum light intensity for mass culture of the brackish-water cyclopoid copepod Paracyclopina nana, survival, growth, and productivity of the copepod were examined at several light intensities (0, 10, 100, 500, 1,000 lx). The survival rate of P. nana from nauplius to adult decreased with increasing light intensity. The highest survival rate was found under the dark condition, with 61.7% surviving; no significant difference was observed between 0 and 10 lx (51.7%) and the lowest survival rate was with 100 lx (26.7%). Survival rates at 500 and 1,000 lx were significantly lower in comparison with other conditions. The developmental period from nauplius to copepodid (5.8 days) and to adult (11.8 days) at 10 lx was significantly shorter than in the other treatments. Daily mean nauplius production of adult females over 7 days at 0, 10 and 100 lx was significantly higher than at 500 and 1,000 lx. In the 1,000 lx treatment, 99% of the adult females died on the $14^{th}$ day. The optimum light intensity for the mass culture of P. nana could be 10 lx, which had no adverse effects on survival, development, or reproduction.

• Ocean Science Journal
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• v.40 no.1
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• pp.55-59
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• 2005

We cloned the complete cDNA of the ${\beta}-bubulin$ from the soft coral, Scleronephthya gracillimum $(K\ddot{u}kenthal)$ (Alcyonacea, Octocorallia, Anthozoa, Cnidaria), via the random sequencing of a cDNA library and the 5'-rapid amplification of cDNA end (RACE) technique. The full-length cDNA of the S. gracillimum ${\beta}-tubulin$ comprised 1541 bp, not including the poly $A^+$ stretch, also contained a complete open reading frame, which codes for a total of 445 amino acids. The amino acid residues 16402 appeared to be in a state of conservation in a variety of animals. Northern blot analysis clearly demonstrated that the sequence we have obtained is, indeed, the full-length cDNA of the ${\beta}-bubulin$ gene in S. gracillimum.

• Atmosphere
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• v.21 no.4
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• pp.439-446
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• 2011

NCEP reanalysis data were analyzed in order to provide distribution of global wind resource and wind speed in the surface layer for the years 2000-2009. Wind speed at 10 m above ground level (AGL) was converted to wind speed at 80 m above the ground level using the power law. The global average 80 m wind speed shows a maximum value of $13ms^{-1}$ at the storm track region. High wind speed over the land exists in Tibet, Mongolia, Central North America, South Africa, Australia, and Argentina. Wind speed over the ocean increased with a large value in the South China Sea, Southeast Asia, East Sea of the Korea. Sea surface wind in Western Europe and Scandinavia are suitable for wind farm with a value of $7-8ms^{-1}$. Areas with great potential for wind farm are also found in Eastern and Western coastal region of North America. Sea surface wind in Southern Hemisphere shows larger values in the high latitude of South America, South Africa and Australia. The distribution of low-resolution reanalysis data represents general potential areas for wind power and can be used to provide information for high-resolution wind resource mapping.

• Atmosphere
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• v.19 no.1
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• pp.67-78
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• 2009

A strong negative correlation has been detected between the North Pacific Oscillation Index (NPI) and the Effective Drought Index (EDI) in May over Korea. In May of positive NPI year, anomalous patterns caused a drought in Korea as follows: the anomalous south-low, north-high low-level pressure patterns in the northeast and southeast of Korea have strengthened the anomalous northerlies to Korea. In addition, these anomalous northerlies have prevented western North Pacific (WNP) high from moving northward. As a result, anomalous descending flows have strengthened in the mid-latitude region in East Asia. In the WNP, the anomalous south-high, north-low sea surface temperature (SST) has been widely distributed, which has strengthened anomalous south-low, north-high low-level pressure patterns. These anomalous characteristics of pressure and SST patterns observed in May of positive NPI years have already been detected in previous winter (December-February) and early spring (March, April). In addition, the anomalous negative sea ice concentration in the North Pacific during two seasons has strengthened the anomalous anticyclonic circulation in the same region and in turn made a contribution to formation of anomalous south-low, north-high pressure patterns in May.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.1
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• pp.98-102
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• 2020

We examined the comparative spawning ecology of daggertooth pike conger Mureanesox cinereus and common pike conger M. bagio in the South Sea of Korea from May 2018 to December 2019. In the South Sea of Korea, the mean total length (TL) of M. cinereus was significantly smaller than that of M. bagio. The sex ratios of both species were skewed toward females. The spawning period of M. cinereus was from June to October, while the spawning period of M. bagio was from August to October. The lengths at 50%, 75%, and 97.5% sexual maturity of M. cinereus females were estimated as 54.6 cm, 60.4 cm, and 74.1 cm TL, respectively. It was not possible to estimate lengths at sexual maturity for M. bagio in the South Sea of Korea due to the absence of immature stages.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.5
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• pp.495-499
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• 2003

Age and growth of purpulish Washington clam (Saxidomus purpuratus) was investigated from 480 samples monthly collected from January to December 2002 in Jinhae Bay, Korea. Examination of outer margins of the shell revealed that the translucent zone was formed once a year from March to April, it can be used as annulus. Ages were determined from ring radius of shell, and maximum age of the the clam was 9 years. The spawning period was from May to October, and the main spawning occurred in July. The relationship between shell length (SL) and shell height (SH) was $SH=0.8405{\times}SL^{-4.9709}\;(R^2=0.97)$ and that between the shell length (SL) and total weight (TW) was $TW=0.9580{\times}10-4{\times}SL^{3.220}(R^2=0.97).$ The von Bertalanffy growth equation were $SL_t=125.57(1-e^{-0.2523(t+0.5367)},\;TW_t=549.26(1-e^{-0.2523(t+0.5367)})^{3.220}.$

• Animal Systematics, Evolution and Diversity
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• v.8 no.2
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• pp.243-258
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• 1992

For the systematic study of Korean Asteroidea the specimens collected from total 69 localities in the South Sea, Korea during the period from April, 1980 to Apirl, 1992 were indentified. As a result, 23 species, 18 genea, 8 families and 5 orders were identified of which two species, Mediaster brachiatus and Stellaster equestris have not been reported in Korea yet. Asterina perctinifera was the commonest species collected from 43 localities of 69 localities. Fifteen species were found in Korea Strait and Cheju Island area, respectively. Fifteen temperate species, 7 tropical species and 3 boreal species were found to be distributed in the South Sea of Korea. The asteroids known so far in Korea tuned out to be 43 species.

• Environmental Analysis Health and Toxicology
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• v.20 no.4 s.51
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• pp.333-341
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• 2005

In order to know whether polychaetes could be used as an appropriate organism for the detection of genotoxicity, DNA strand breaks were evaluated in blood cells of a nereidae worm (Perinereis aibuhitensis) exposed to various aquatic chemical pollutants (e.g. Cd, Pb, Pyrene, Benaor[a]pyrene). Hydrogen peroxide increased DNA strand breaks up to the highest concentration (10 $\mu$M). Higher concentration than 0.1 $\mu$M showed a significantly more DNA damage than control. Cadmium and lead also showed higher DNA damage than control, over 1.0 and 1 $\mu$g/L, respectively. In case of pyrene, DNA damage was detected even at 0.001 $\mu$g/L. However, DNA damage decreased due to apoptosis at the highest concentration of pyrene and Pb. This study suggested that the polythaetous blood cells could be used effectively for screening genotoxic contaminants in the environment.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.237-240
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• 2004

When the concrete structures are in contact with seawater, concentration of chloride for estimating chloride diffusion coefficient can be defined as the chloride concentration of sea water. However, in case the concrete structures, constructed in the seashore, aren't directly in contact with seawater, it is difficult to establish the interface concentration of chloride. In addition, marine concrete structures are greatly affected by salt attack such as rebar corrosion, among the cause of salt attack, airborne sea salt is primary factor. Therefore, in this study, salt attack environment by airborne sea salt was investigated in terms of a seasonal distribution at 33 spots, 6 areas in the East, West, South coast for 1 year. Results indicated that in the South coast, the amount of the airborne sea salt is comparatively higher in summer. in the West coast. higher in winter. On the other hand, in the East coast, the amount of the airborne sea salt is rarely affected by a season.

• Animal Systematics, Evolution and Diversity
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• v.24 no.1
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• pp.139-142
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• 2008

A lysianassid species, Orchomene japonicus (Gurjanova, 1962) associated with sea squirts collected from Geojedo Island located in the South Sea of Korea, is described and illustrated. Present specimens conform to that of Gurjanova's except some morphological variation in mandibular palp.