• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.497-498
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• 2000

The venus clam, Ruditapes philippinarum, is an aquaculture shellfish mainly distributed in an intertidal zone of East Asia including Korea, China and Japan. The morphological variation of this species is great. In fact, two of the most popular markers used in molecular evolution, mitochondrial DNA (mtDNA) and nuclear ribosomal DNA (rDNA), have quite different properties, which could translate into different consequences of mutation, drift, migration and selection on patterns of geographical variation and molecular divergence. (omitted)

• Nuclear Engineering and Technology
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• v.36 no.3
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• pp.229-236
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• 2004

Radiation hardening is a multiscale phenomenon involving various processes over a wide range of time and length. We present a multiscale model for estimating the amount of radiation hardening in pressure vessel steel in the environment of a light water reactor. The model comprises two main parts: molecular dynamics (MD) simulation and a point defect cluster (PDC) model. The MD simulation was used to investigate the primary damage caused by displacement cascades. The PDC model mathematically formulates interactions between point defects and their clusters, which explains the evolution of microstructures. We then used a dislocation barrier model to calculate the hardening due to the PDCs. The key input for this multiscale model is a neutron spectrum at the inner surface of reactor pressure vessel steel of the Younggwang Nuclear Power Plant No.5. A combined calculation from the MD simulation and the PDC model provides a convenient tool for estimating the amount of radiation hardening.

• Bulletin of the Korean Space Science Society
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• 2009.10a
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• pp.36.1-36.1
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• 2009

We investigate the molecular and atomic gas properties of 20 Virgo cluster spiral galaxies by comparing with optical properties to assess the effect of the Virgo environment on the interstellar media of the Virgo disks. CO maps from FCRAO On-The-Fly (OTF) mapping survey and HI maps from VIVA (VLA Imaging of Virgo spirals in Atomic gas) are shown, and radial properties of molecular and atomic gas are compared. H2 deficiency along with HI is investigated, and gas evolution history of the Virgo cluster spirals is also examined.

• Animal Systematics, Evolution and Diversity
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• v.12 no.4
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• pp.359-374
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• 1996

The speciemens of Daphnia obtusa collected from various freshwater habitats at 13 localities in South Korea during the period form May 1980 to May 1996 were examined. In this paper D. obtusa in Korea is described and figured, and discussed with distribution and ecology.

• Animal Systematics, Evolution and Diversity
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• v.12 no.4
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• pp.349-358
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• 1996

Six bdelloid rotifers are newly recorded from Korea: Philodina vorax, Philodina flaviceps, Philodina acuticornis odiosa, Didymodactylus carnosus, Macrotrachela multispinosa crassispinosa, Macrotrachela papillosa. All these are fully redescribed and illustrated.

• Animal Systematics, Evolution and Diversity
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• v.14 no.3
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• pp.293-309
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• 1998

A taxonomic study for clarifying the decapod fauna of Gejedo Island, Korea was performed. Seventy nine species in 28 families were identified through the present investigation and of which 9 species of shrimps, 7 species of anomurans, and 39 species of crabs are newly added to the decapod fauna of this area. With the previously known 40 species, a total of 93 decapod species from this island and its adjacent islets are listed, and Pugettia quadridens intermedia Sakai, 1939 is redescribed with illustrations. The zoogeographical aspects of Geojedo Island are also discussed based on the composition of geographical forms of brachyuran decapods.

• Proceedings of the Korean Society of Life Science Conference
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• 2002.03a
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• pp.97-97
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• 2002

• Animal Systematics, Evolution and Diversity
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• v.34 no.4
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• pp.208-214
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• 2018

The genus Luidia belongs to the family Luidiidae in the order Paxillosida. It is a common littoral taxon, and the depth range of the Korean fauna is generally 0-100 m. However, specimens of Luidia were collected from Jeju Island in Korea at 150-160 m depth and identified as Luidia sagamina sagamina $D{\ddot{o}}derlein$, 1920. This species is determined by morphological characteristics and mitochondrial cytochrome c oxidase subunit I sequence analysis. Luidia sagamina sagamina is a very rare sea star in worldwide and it only collected previously from Sagami Bay, Japan, and is newly reported in Korea. Four species of Luidia, including L. s. sagamina, are recorded in the Korean fauna.

• Animal Systematics, Evolution and Diversity
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• v.35 no.4
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• pp.186-190
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• 2019

DNA barcoding of two marine tintinnids, Eutintinnus rectus and Schmidingerella arcuata, was performed using four samples collected from different sites in the north-eastern coast of South Korea. The loricae morphology was observed by light and scanning electron microscopy. Molecular data were analyzed using five nuclear ribosomal DNA markers(18S, ITS1, 5.8S, ITS2, and 28S genes) and one mitochondrial marker (CO1 gene). The intraspecific pairwise differences of E. rectus and S. arcuata in the CO1 gene were 0.0-0.2% and 0.0-0.6%, respectively, while there were no differences in the 18S rDNA sequences.

• Animal Systematics, Evolution and Diversity
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• v.8 no.2
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• pp.183-188
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• 1992

Gitanopsis koreana, new species collected at Ganggu and Sadong in Korea is described and illustrated. This species is very close to G. robastodentes Hirayama, 1983 from west Kyushu, Japan. But, this new species is distinguished from G. robastodentes by the shorter ventrodistal extension of article 2 of gnathopod 2 and the shorter telson.