• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.1
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• pp.79-83
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• 2014

Thirty five juveniles belonging to the genus Collichthys were collected using a bag net at Gang-wha-do, in the eastern Yellow Sea, between July and September, 2012, and identified using combined genetic and morphological methods. We sequenced 316 base pairs of mitochondrial DNA cytochrome c oxidase subunit I of 35 individuals, of which 22 individuals were identified as Collichthys niveatus (12.9-47.6 mm in SL) and 13 as Collichthys lucidus (13.4-40.3 mm SL). Morphologically, the number of occipital crests, an important taxonomic character during the adult stage, could not distinguish the two species during the juvenile stage, but the shape of the first anal fin spine clearly distinguished the two species even among juveniles.

• Korean Journal of Plant Taxonomy
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• v.41 no.3
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• pp.271-279
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• 2011

The morphological characteristics of the Korean Scopolia japonica Maxim., commonly known as 'Mi-chi-gwang-i-pul' in Korean, were re-evaluated in comparison with results from previous research, while the distribution map was formulated according to existing flora and voucher specimens. The result of the re-evaluation has shown that there are some distinctive discrepancies compared to the previous reports of some characteristics such as the color of the basal stem, numbers of lateral veins, apex shape of calyx and corolla including the color of corolla. The Korean Scopolia japonica Maxim is found throughout Korea except Jeju-do province. The intra-specific species such as S. parviflora (Dunn.) Nakai, S. lutescens Y.N. Lee and S. kwangdokensis Y.N. Lee were treated as synonyms of S. japonica Maxim. in this research.

• Korean Journal of Ichthyology
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• v.24 no.4
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• pp.287-291
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• 2012

To verify the validity of Hemiculter eigenmanni (Jordan and Metz, 1913), we conducted morphological analysis on two syntypes of Hemiculter leucisculus (Basilewsky, 1855) and holotype of H. eigenmanni. Although some morphological differences were recognized between two nominal type specimens, it is concluded intraspecific or geographic variation through comparison with many specimens collected from Korea. Previously suggested synonymy between H. leucisculus and H. eigenmanni was reconfirmed, therefore the latter becomes a junior synonym of the former.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.102.2-102.2
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• 2011

Sunspots usually appear in a group which can be classified by certain morphological criteria. In this study we examine the moments which are statistical parameters computed by summing over every pixels of contours, in order to quantify the morphological characteristics of a sunspot group. The moments can be additional characteristics to the sunspot group classification such as McIntosh classification. We are developing a program for image processing, detection of contours and computation of the moments using continuum images from SOHO/MDI. We apply the program to count the sunspot numbers from 303 continuum images in 2003. The sunspot numbers obtained by the program are compared with those by SIDC. The comparison shows that they have a good correlation (r=89%). We are extending this application to automatic sunspot classification (e.g., McIntosh classification) and flare forecasting.

• Korean Journal of Plant Taxonomy
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• v.41 no.2
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• pp.156-163
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• 2011

The morphological characteristics of Chionanthus retusus Lindl. & Paxton in Korea are reviewed in this study through the comparison with its previous records and a distribution map of this species is created using previous flora and voucher specimens. The leaf epidermal micromorphology and the petiole anatomy are also briefly described.

• Journal of Plant Biology
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• v.6 no.1
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• pp.1-7
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• 1963

Two individuals of intergeneric hybrids in the crossing of Brassica pekinensis ♀$\times$Raphanus sativus ♂ were obtained, and among the three kinds of plants, Brassica, Raphanus, and F1, comparison on the mega- and microsporogenesis, megagammetophyte formation, and morphological changes in the developing sporangia, etc., were made. Differences between Brassica and Raphanus were observed in the shape of mega- and microsporangia, their changes in development, and the formation of megagametophyte. Sporangia of the F1 plants, until pre-meiotic stage, show intermediate, maternal, paternal, or vigorous inclination, and the difference of these characteristics when compared with those of the parent is slight. Meiotic irregularity resulted from the intergeneric hybridity of F1 plant gives rise to the abnormal mega- and microspore and accompanied abortive female and male gametophytes, bringing about the remarkable differences from its parent in the morphological changes of the developing mega- and microsporangia.

• The Korean Journal of Zoology
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• v.30 no.4
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• pp.417-431
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• 1987

Isozyme analysis, morphometric comparison, and artificial hybridization test wereperformed to elucidate the patterns of genic variation, morphological differentiation, genetic incompatibility, and a probable path in speciation between two MDH allelotypes (MM type and MS type) of the Dark Chub Zacco temmincki, a fresh water fish inhabiting in Korean waters. The degree of genic variation of MS type(HD=.023, HG=.021) was twofold higher than that of MM type (HD=.013, HG=.014) but both allelotypes were far less than the average genic variation of fresh water Bish in general. The average genetic similarities among 7 populations of MM type and 6 Populations of MS type were S=.947 and S=.966 respectively, whereas the value between two allelotypes was S=.853. Presumed divergent time of two allelotypes was estimated to be about 700 thousand years ago. Discriminant function analysis based on 18 morphometric characters of 302 specimens representing 12 populations revealed no morphological difference between two allelotypes. Artificial hybridization test indicates that there is an obvious genetic incogpatibility between two allelotypes and therefore it is assumed that isolating mechanism is completed.

• Journal of the Institute of Convergence Signal Processing
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• v.12 no.2
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• pp.91-95
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• 2011

In this paper, we present an improved multi-scale gradient algorithm. The proposed algorithm works the effectively handling of both step and blurred edges. In the proposed algorithm, the image sharpening operator is sharpening the edges and contours of the objects. This operation gives an opportunity to get noise reduced image and step edged image. After that, multi-scale gradient operator works on noise reduced image in order to get a gradient image. The gradient image is segmented by watershed transform. The approach of region merging is used after watershed transform. The region merging is carried out according to the region area and region homogeneity. The region number of the proposed algorithm is 36% shorter than that of the existing algorithm because the proposed algorithm produces a few irrelevant regions. Moreover, the computational time of the proposed algorithm is relatively fast in comparison with the existing one.

• Korean Journal of Environmental Biology
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• v.39 no.1
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• pp.6-15
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• 2021

Various biometric and geometric measures were used to discriminate between the morphologically similar river puffer, Takifugu obscurus, tiger puffer, T. rubripes, their hybrids, and their triploid hybrids. The hybrids and triploid hybrids had greater anal fin width, nostril width, and snout length than the parental species (p<0.05). However, they had less caudal peduncle depth, inter-orbital width, head length, and head width(p<0.05). The morphometric and meristic characteristics of the hybrids and triploid hybrids were either intermediate between the parental species or more similar to those of one parental species. However, the external morphology of the hybrids and triploid hybrids was predominantly maternal. The triploid hybrids had asymmetry in the fin rays and gill raker numbers. This study identified phenotypic characteristics by distinguishing the morphological variables of river puffer, tiger puffer, their hybrids, and their triploid hybrids.

• Animal Systematics, Evolution and Diversity
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• v.37 no.3
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• pp.229-234
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• 2021

Scolelepis (Scolelepis) daphoinos is newly reported in Korean fauna. This species can be distinguished from its congeners by the following characteristics: the presence of reddish pigment patches on the posterior part of the prostomium, notopodial postchaetal lamellae that are partially fused to the branchiae, and the presence of only the bidentate hooded hooks. The morphological diagnosis and photographs of S. (S.) daphoinos are provided. The partial mitochondrial cytochrome c oxidase subunit I (COI), 16S ribosomal DNA(16S rDNA), and the nuclear 18S ribosomal DNA (18S rDNA) sequences from Korean specimens of S. (S.) daphoinos were determined. Species identification was supported by a comparison of DNA barcode sequences of COI and 16S rDNA with morphological examination from the specimens of type locality, China.