• Animal Systematics, Evolution and Diversity
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• v.29 no.2
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• pp.191-197
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• 2013

Specimens of nudibranchs have been surveyed by scuba diving from 9 localities along the Korean coast. By examination of morphological characteristics, four species in the superfamily Doridoidea which are new to Korea were identified, and re-described: Thorunna florens (Baba, 1949), Diaulula sandiegensis (Cooper, 1863), Jorunna parva (Baba, 1938), and Doris odhneri (MacFarland, 1966). In addition, radulae of three species were observed and photographed by using scanning electron microscopy. As a result of the study, 16 species of doridoidean nudibranch are now known from Korean waters.

• Animal Systematics, Evolution and Diversity
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• v.34 no.1
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• pp.64-68
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• 2018

The genus Callochiton Gray, 1847 is small to medium sized chiton (up to $55{\times}36mm$ in size) and includes approximately 30 species worldwide, most of which are found on hard substrata in subtidal zone. To date, only three species of Callochiton Gray, 1847 have been reported in Japan. In this study, we found C. foveolatus(Is. Taki, 1938) as first record of the family Callochitonidae Plate, 1901 in Korea and its morphological features were described and compared with other northwestern Pacific species. In addition, the partial fragment of mitochondrial DNA cytochrome c oxidase subunit I sequences of C. foveolatus was determined as DNA barcoding record and compared with other congeneric species.

• Proceedings of the Korean Vacuum Society Conference
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• 2003.08a
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• pp.68-68
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• 2003

• 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)

• Journal of The Korean Astronomical Society
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• v.13 no.1
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• pp.45-62
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• 1980

Defining a metal parameter $(Sp)_c$, which is related to the morphological parameters of C-M diagrams, we have estimated metal abundances for 97 globular clusters in our Galaxy. A correlation between absolute magnitude of the horizontal branch and metal abundance is derived, which is used for the determining distances to globular clusters whose visual magnitudes of the horizontal branch are known. The space distribution of globular clusters and the chemical evolution of the halo are examined. Our analysis suggests an initial mean gradient of metallicity to be d[Fe/H]/$dr_G$ = -0.06 $kpc^{-1}$ for the halo in galactocentric distance, $r_G$<20 kpc. Our findings also imply a slow collapse of protogalaxy.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.73.1-73.1
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• 2011

An understanding of the ultraviolet (UV) properties of nearby galaxies is essential for interpreting images of high redshift systems. In this respect, the prediction of optical-band morphologies at high redshifts requires UV images of local galaxies with various morphologies. We present the simulated optical images of galaxies at high redshifts using diverse and high-quality UV images of nearby galaxies obtained through the Galaxy Evolution Explorer (GALEX). We measured CAS (concentration, asymmetry, clumpiness) as well as Gini/M20 parameters of galaxies at near-ultraviolet (NUV) and simulated optical images to quantify effects of redshift on the appearance of distant stellar systems. We also discuss the change of morphological parameters with redshift.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.54.2-54.2
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• 2012

Solid-state dewetting of thin films is a process through which continuous solid films decay to form islands. Dewetting of thin films has long been a critical issue in microelectronics and much effort has been made to prevent the process and enhance the stability of films. On the other hand, dewetting has also been purposely induced to create arrays of particles and other structures for applications, including plasmonic structures and catalysts for growing nanotube and nanowire. We have investigated ways of producing regular structures via templated dewetting of thin films. Mainly, two different approaches have been used in our works to template dewetting of thin films: periodic topographical templating and planar patterning of epitaxially-grown films. Dewetting of topographically-patterned thin films results in the formation of nanoparticle arrays with spatial and crystallographic orders. Morphological evolution during templated-dewetting of single crystal films occurs in deterministic ways because of geometric and crystallographic constraints, and leads to the formation of regular structures with smaller sizes and more complex shapes than the initial patches. These results will be reviewed in this presentation.

• Journal of Powder Materials
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• v.6 no.1
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• pp.49-55
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• 1999

Al-Cr-Zr nanocomposite metal powders were prepared by mechnical alloying (MA) in order to develop aircraft structure materials with lighter weight and lower cost than the conventional Ti and Ni alloys. The morphological changes and microstrutural evolution of Al-6wt.%Cr-3wt.%Zr nanocomposite metal powders during MA were investigated by SEM, XRD and TEM. The approximately 50$\mu$m sized Al-Cr-Zr nanocomposite metal powders has been formed after 20 h of MA. The individual X-ray diffraction peaks of Al, Cr and Zr were broadened and peak intensitied were decreased as a function of MA time. The observed Al crystallite size by TEM was in the range of 20 nm, which is a simliar value calculated by Scherrer equation. The microhardness of Al-Cr-Zr nanocomposite metal powders increases alomost linearly with increase of the processing time, reaching a saturation hardness value of 127 kg/$mm^2$ after 20 h of processing. The intermetallic compound phase of $Al_3Zr_4$ in the matrix was identifed by XRD and TEM.

• Animal Systematics, Evolution and Diversity
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• v.13 no.2
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• pp.173-192
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• 1997

Three damselfishes, Dascyllus melanurus, Dascyllus trimaculatus and Poamcentrus nagasakiensis were collected in the coastal waters of Cheju Island, Korea, during the period from July 1994 to May 1997. These taxa were a new records to th Korean fish fauna. This study re-describe about family Pomacentridae (6 genera, 13 species) including 3 new recorded species and suggest the taxonomic key of family pomacentridae from Korea.

• Animal Systematics, Evolution and Diversity
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• v.18 no.1
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• pp.121-125
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• 2002

Oligotoma saundersii(Westwood, 1837) was recognized on the bark of Pachira aquatica Aubl.(Bombacaeae), an ornamental tree growing in greenhouse, Seoul, Korea. The morphological characteristics and biology of O. saundersii are presented. This is the first record of the order Embiidina in Korea.