• Journal of Wetlands Research
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• v.20 no.3
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• pp.243-248
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• 2018

This study was carried out to clarify changes in community structure of Quercus acutissima dominant stand on the south slope of Mt. Danseok-san with fixed twenty quadrates. Five field surveys were conducted from Aug. 1999 to May 2018. During the period, the density lessened to 0.20 in 2012 comparing with 0.33 in 1999. However recent field study in 2018 showed moderate rising to 0.24. In 1999, the DBH class distribution of all trees formed reverse J curve. However, the reverse J curve was torn down, forming bell curve. In 2018, the curve showed similar shape of reverse J shape on the group of young trees, forming bell shape on the group of mature trees. It reveals that DBH 13cm is on the threshold of trees competition trend where the downtrend in the trees are on uptrend. The most dominant Q. acutissima formed bell curve. The peak of the curve shows the shift to the right of the graph as it gets lower by year.In case of Q. mongolica, shows a change in the shape of a low bell as the distribution curve increases. The oak stand in this study is in the process of changing from the initial stage of the secondary forest succession to the intermediate stage. The most dominant tree is Q. acutissima, and the sub-dominant tree is Q. mongolica in present. Considering the age distribution of the two competing tree species, the succession of this stand is expected to transfer to the Q. mongolica-dominant community.

• Korean Journal of Plant Taxonomy
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• v.46 no.3
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• pp.288-294
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• 2016

The Vietnamese occurrence of Stephania subpeltata H. S. Lo (Menispermaceae) is reported here for the first time. It is morphologically allied to S. japonica but differs in having subpeltate, ovate deltoid or broadly deltoid to subdeltoid leaves, shorter petiole, fewer leaf veins, conspicuously pedicellate umbelliform cymes which are seldom compound, and purple flowers and endocarp with a reduced number of abaxial rows. A taxonomic description, distribution details, ecology, and a key to the Vietnamese species of Stephania are provided.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.5 s.149
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• pp.550-559
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• 2006

A design procedure for a ship with minimum total resistance was developed using a numerical optimization method called SQP(Sequential Quadratic Programming) and a CFD technique based on the Rankine source panel method with the nonlinear free surface boundary conditions. During the whole optimization process the geometry of the hull shape was represented based on the NURBS(Non-uniform rational B-spline) technique and the modification of the hull shape was controlled using the Bell-shaped distribution function to keep the fairness of the hull shape before and after the hull modification. The numerical analysis was carried out using 4000TEU container ship in the towing tank facility installed in the Pusan national university to know the validity of the developed algorithm for this study. As the results of the numerical analysis it proved that the resistance of the optimized hull is conspicuously reduced in comparison with the original hull in a wave-making resistance point of view.

• Korean Journal of Plant Taxonomy
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• v.43 no.4
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• pp.300-311
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• 2013

Subalpine species, Sorbus pohuashanensis in the Korean peninsula, which is assumed to be evolved from hybridization between S. commixta and an unknown species based on the flavonoids data. Morphometric analysis was conducted on the basis of 19 leaf and flower (or fruit) characters. A total of 721 samples in 13 populations of Sorbus pohuashanensis and S. commixta from Korea and additional specimens of S. commixta, S. pohuashanensis, and S. wilsoniana from Japan and China were examined to reveal the hybridization patterns and morphological differences. We found a preliminary evidence where Korean mountain rowan is more related to a Chinese inland taxon, S. wilsoniana, rather than Northeastern Chinese S. pohuashanensis in terms of flavonoids. The current morphological structure of the Korean mountaion rowan, however, which is more similar to S. commixta, was neither associated with that of S. wilsoniana nor that of S. pohuashanensis. This indicates that this morphological variation represents an intermediate of S. commixta and S. wilsoniana via a more ancient hybridization event in terms of qualitative characters, such as stipules, buds, and carpels. These morphometric differences together with other distinguishing characteristics suggest that the Korean mountain rowan should be considered as a conspecific species of S. commixta, although this demonstration of hybridization with the current phenetic species concept contradicts longstanding historical species concept.

• Korean Journal of Plant Taxonomy
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• v.44 no.2
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• pp.77-80
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• 2014

Here we report a previously unrecorded species of Korean Myriophyllum L. (Haloragaceae). This taxon, M. oguraense Miki has been regarded as a Japanese endemic for some 60 years. Myriophyllum oguraense and its closely related M. verticillatum L. share the characteristic of having pectinate emergent leaves that are similar in shape to, but much smaller than, the submerged leaves. However, the primary characteristic that differentiates these taxa is the turion shape (club shaped in M. verticillatum and linear in M. oguraense). The common name, 'Gin-dong-a-mul-su-sae-mi' was also newly given considering its characteristic turion shape. Photographs and a key to Korean Myriophyllum species are provided in addition to complete descriptions including information on nomenclatural types, distributions and specimens examined.

• Korean journal of applied entomology
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• v.37 no.1
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• pp.39-48
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• 1998

To know whether there is any androconia on Korean Lycaenidae, studies were carried out with Korean Lycaenid butterflies for their types and distribution pattern with the aid of scanning electron microscope. As the results, androconia was observed from 8 species; Niphanda fusca (B. et G.), Pseudozizeeria maha (K.), Zizina otis (F.), Everes argiades (P.), Celasrtina argiolus (L.), Maculinea arionides (S.), M. teleius (B.) and Lycaeides argyronomon (B.). Androconia was not found only from males, and it was observed on both dorsal and ventral surfaces of fore wings and on ventral surface of hind wings. Androconia was found to be distributed mainly on the area between the median and anal venis. General structure of androconia on Korean Lycaenids was rather simple with laminar and foot stalk. However, 2 types of androconia were observed from 2 species, Pseudozizeeria maha and Everes argiades, while only one type was observed from other 6 species. The foot stalks of androconia on Niphanda fusca under the tribe Niphandini is located on the ventral surface of laminar and hidden from dorsal view, while one end of that on all other 7 species belong to the tribe Polyommatini is attached to the lower side of laminar and shown from both side.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.210-210
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• 1999

그리드 전압을 +20V에서 -20V까지 변화시켜 줌을 이용해 확산 영역의 전자의 온도를 2-0.6eV까지 제어할 수 있었으며, 전자 밀도는 1010cm-3 - 1011cm-3, 플라즈마 전위는 3-25V까지 제어할 수 있었다. <그림1>은 실험결과이다. 그 외 전자의 온도는 입력 전력의 주파수 및 크기에는 거의 무관하나 압력에 반비례하였으며, 밀도는 전력의 크기에 비례하고, 압력에 반비례하나, 전력의 주파수에는 무관하였다. 그리드 전압이 20V에서 -20V로 변함에 따라 전자의 온도가 떨어져 높은 에너지를 가진 전자들이 줄어들게 되어 CF3+의 양은 많아지고 CF2+와 CF+의 양은 상대적으로 줄어들어 CF3+와 CF2+ 비는 4-18 CF3+와 CF+ 비는 2-5까지 변화하였으며, 변화모양은 전자 온도에 크게 의존하였다. <그림2>는 결과를 나타낸 것이다. 그 외 CF3+ / CF2+ 와 CF3+ / CF+는 입력 전력의 크기에 반비례하며, 압력, 가스 주입량에 따라서도 이온들의 분포 변하였다. 그러나 입력 전력의 주파수와는 무관하였다. Appearance mass spectrometry를 이용한 결과 CF, CF 중성종의 분포도 그리드 전압에 따라 변하여 그리드 전압이 높은 경우 더 많이 존재하였다.

• Korean Journal of Plant Taxonomy
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• v.48 no.3
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• pp.163-171
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• 2018

In Korea, Hypodematium glanduloso-pilosum was formerly known as the only Korean native species in the genus. Recently, however, we reported one unrecorded taxon, H. squamuloso-pilosum Ching, which was found on rocks at a limestone mountain in Yeongwol, along with one new taxon, H. angustifolium in Okcheon. Traditionally, Hypodematium taxa are often distinguished from each other by vegetative characters such as pinnatifid lamina, glandular hairs, and narrower or linear lanceolate scales on stipe bases. H. glanduloso-pilosum, distributed widely throughout the country except on Jejudo Island in Korea, exhibiting variations in leaf segregation, indusia positions, hair distributions and size. The high variation in the morphological characters in the widely distributed taxon has caused problems delimitating three native species from each other. To evaluate the phylogenetic relationships among H. glanduloso-pilosum and taxa related to Hypodematium (all Korean native taxa), we carried out morphological and molecular analyses (cpDNA rbcL and psbA-trnH) of populations of the genus Hypodematium in Korea. Although H. glanduloso-pilosum exhibits high variations in some morphological characters, the species is characterized by stipes and indusia with densely multicellular hairs and rod-shaped glandular hairs or hairs and lanceolate or oblong lanceolate scales in rhizomes and stipe bases distinguished from those of other Korean native taxa (H. squamuloso-pilosum and H. angustifolium). In the analyses of cpDNA data, three Korean native taxa are placed in the same clade, i.e., in the glanduloso-pilosum group. Moreover, our analyses propose that H. squamuloso-pilosum (China and Korea), H. angustifolium (Korea), and H. fordii (China and Japan) share the same glanduloso-pilosum clade with H. glandulosopilosum (China, Korea, and Japan).

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.197-198
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• 2010

The morphological and ecological characteristics of Russula eburneoareolata Hongo is reported first time in Korea. The fungus was collected from the mixed forest of Fagaceae in the Gyeryongsan Mountain National Park. The pileus is champagne to ivory, convex then expanded and depressed in the center afterward, and 4 to 9 cm broad. Stipe is 3 to 6 cm long, 12 to 20mm thick and tapering below. Spores are $7-8{\times}6-7\;{\mu}m$, subspherical oval and warty with some connecting lines. Basidia are about $35-40{\times}10-11\;{\mu}m$ and four-spore bearing type.

• Korean Journal of Ichthyology
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• v.24 no.4
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• pp.247-252
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• 2012

Structure on the feeding organs in two Korean ricefishes, Oryzias latipes and O. sinensis, was examined in the jaws and the teeth. In the jaw, O. latipes has a dent on the dorsal edge of distal arm of premaxilla (vs. straight in O. sinensis) and a alveolar arm of premaxilla running in straight line with distal arm of premaxilla (vs. ventra line in O. sinensis). O. latipes has also a dent on the posterior edge of dentary which is connected to coronoid process of dentary (vs. straight in O. sinensis). Large teeth developing only in the male, which is sexual dimorphism, developed into outside direction of the mandible in O. latipes (vs. dorsal direction in O. sinensis). In the teeth forms, O. latipes has two types (conical type and arrowhead type), whereas O. sinensis has only one type (conical type). Through this study, we confirmed that two Korean ricefishes show distinctive characteristics in the structure of the feeding organs.