• Korean Journal of Pharmacognosy
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• v.38 no.1
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• pp.1-9
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• 2007

This study was conducted to investigate the native Phytolacca insularis in Ulleung Island for their distribution and ecological characteristics. P. insularis, called as "Sum-Ja-Ri-Gong", is very rare plant which is only restricted in Ulleung Island. It is a plant out of 217 endangered plant species designated by the Korea Forest Service (1996). The native sites were discovered several plants in the small communities at the area from 32m to 116m above the sea level in the seashore of Ulleung Island. The average vegetation height of herb layer in the native sites was 0.77m and average coverage percentage of vegetation layer was 75.56%. Average 11.89 species were emerged on a plot. P. insularis has a tendency to emerged with Galium spurium var. echinospermon and Artemisia lavandulaefolia community.

• Korean Journal of Remote Sensing
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• v.26 no.6
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• pp.675-680
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• 2010

Temperature is one of the main issues in climate change, and the urban heat island effect in highly developed urban areas is an important issue that we need to deal with. This study analyzed the extent of the cooling effects of urban green spaces. The study used a surface temperature map of Seoul. It found that the cooling effects of green space was observed within limited distances, although it varied a little depending on the parks investigated. The cooling effect distance ranged from 240m to 360m, averaging about 300m. It also found the size of an urban green space does not make much difference in cooling the surrounding areas. Although further investigation with diverse urban areas should be conducted on this matter, the results did imply that many small green spaces in the neighborhood are more effective than a single big green space in mitigating the heat island effects of cities.

• Journal of the Korean association of regional geographers
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• v.19 no.2
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• pp.223-233
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• 2013

Yeonpyeong Island, an island of Ong-jin County, is a very important and meaningful area in terms of its geo-politics and natural environment. But in spite of well preserved natural environment, because of limited access and security risk, there were little researches. In this sense this study would be meaningful for inquiring into the regional geomorphology of Yeon-pyeong Island. The major findings of this study are as follows. 1) 12 sites among 20 sites was evaluated 1st grade, and this means that geomorphic value of Yeon-pyeong Island is very excellent. 2) Coastal landforms of Yeon-pyeong Island are classified three major types which are rocky coast which consist of wave-cut platform and sea cliffs, sand or shingle beaches and coastal plain in the embayment area, and tidal flat areas and small uninhabited islands. 3) Cross sectional shape of Yeon-pyeong Island is asymmetric, since coastal erosion of island concentrate on the northern and western shore. 4) Quality and value of tidal flats will be deteriorate unless the dyke construction is stopped.

• Animal Systematics, Evolution and Diversity
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• v.23 no.1
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• pp.39-44
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• 2007

Two new marine sponges, Clathria (Clthria) jungtaedoensis n. sp. and Antho (Antho) hataedoensis n. sp. were collected in Taedo Island, Korea. C. (C.) jungtaedoensis n. sp. is similar to C. (C.) striata. The new species, however, has many small toxa and massive form. A. (A.) hataedoensis n. sp. is similar to A. (A.) inconstans from Gulf of Naples, Italy, but differs from the latter in the size of spicules. The toxa in the new species is about one third as long as A. (A.) inconstans's.

• The Plant Pathology Journal
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• v.16 no.1
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• pp.43-47
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• 2000

Citrus tristeza virus (CTV) is the causal agent of one of the most important diseases of citrus. Recently, CTV has been detected in Cheju Island by ELISA. The coat protein (CP) gene of CTV isolated form Cheju Island was cloned by RT-PCR and the nucleotide was analyzed in this study. Citrus leaves were collected from trees showing decline symptoms from various region of Cheju Island in the summer of 1998 and 1999. The CP gene open reading frame is composed of 670 nucleotides and encodes a polypeptide of 223 amono acids. Sequence analysis the CP gene revealed that two CTV strains present in Cheju Island. Viruses collected form Sogwipo area and Cheju City area in 1999 ahowed 91-93% nucleotide sequence homology with CTV T36 strain. Viruses collected form Cheju City area in 1999 and Sogwipo City in 1998 showed 94-98% nucleotide sequence homology with CTV SY568 strain. A efficient viral RNA extraction methods was developed by modifying procedure for animal virus RNA purification methods and PCR product was detected form one tenth of RNA purified from as small as 45 mg fresh or frozen tissue.

• 한국해양학회지
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• v.22 no.1
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• pp.9-18
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• 1987

A number of hydrographic studies and some recent current measurements around Chejudo Island suggest an existence of a clockwise residual flow in the west and north coasts of the island all the year round. On the eastern side of the island the Tsushinma Current flows northward and northeastward. The contribution of tide-induced residual currents to the observed residual. flow around the island was examined here through numerical solution of the two-dimensional nonlinear shallow-water equations. The calculated tide-induced residual currents show a clockwise circulation around the island. Significant residuals of 2-4cms$\^$-1/are confined over sloping bottom topography around t he island and the far-field residuals are negligibly small. The inclusion of a permanent current into the model was also attempted in order to see the effects of the Tsushima Current system on the residual circulation around the is land. It was found that combined effects of tide-induced residuals and the permanent current field associatedwith the Tsushima Current explain qualitatively not only the observed clock wise residuals in the west and north coasts but also the northward flow on the eastern side of the island.

• Explosives and Blasting
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• v.38 no.4
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• pp.37-45
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• 2020

Todo was an uninhabited island located in the sea of Pusan Newport. It was a small island with the height of 32 m above sea level, and its area including the submerged part was approximately 24,400 ㎡. Unfortunately, the island was located exactly in the middle of the narrow entrance way to the North and South Container Wharfs of Pusan Newport so that a number of ships had to turn quickly to avoid collision with the island, which frequently caused collisions with other ships or cranes. To avoid such a danger and make the water way wider and deeper, the Ministry of Oceans and Fisheries decided to remove the island. This was believed to make even super-large vessels operate safely in the sea of Pusan Newport so that the competitiveness of the port could be highly enhanced. This paper describes in detail the whole process of the removing work, which was the first case of successful underwater blasting operation using bulk emulsion explosives and non-electric detonators to remove a whole island in South Korea.

• Animal cells and systems
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• v.9 no.3
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• pp.113-122
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• 2005

A new species of free-living marine draconematid nematode, Dracogalerus koreanus n. sp., is described from the shallow subtidal coarse sediments and various invertebrates of Jeju Island, Korea. This is the first record of this genus from Korea. Dracogalerus koreanus n. sp. is morphologically most similar to D. cryptocephalus (Irwin-Smith) in having similar head shape (rostrum broadly rounded anteriorly) and eight cephalic adhesion tubes, but differs by the small number of rounded protuberances on the ventral side of non-annulated tail end (5 vs 6), small number of posterior subventral adhesion tubes in male (5-6 vs 8), intermingled somatic setae (5-6 vs absent), spicules (slightly curved and relatively thick vs strongly curved and very slender), and higher 'c' value in male (8.8 vs 7.5).

• Animal Systematics, Evolution and Diversity
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• v.35 no.3
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• pp.123-135
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• 2019

Elaphognathia monodi (Gurjanova, 1936) and Elaphognathia kikuchii Nunomura, 1992 are newly reported based on the materials collected from Wando Island and Jeju Island in Korea, respectively. Elaphognathia monodi is distinguished by the following characteristics: the lateral margin of the cephalon is narrowing posteriorly; the frontal border is slightly concave and has a small mediofrontal process, a pair of superior frontolateral processes, and a pair of inferior frontolateral processes. Elaphognathia kikuchii can be distinguished by the following characteristic features: the lateral margin of the cephalon is narrowing anteriorly; the frontal border has a small mediofrontal process and twelve pairs of simple setae along with concavity.

• Animal cells and systems
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• v.8 no.4
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• pp.289-294
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• 2004

Bupleurum latissimum is a narrowly endemic and endangered plant, restricted to only two small populations on steep cliffs of a small island, Ulleung Island, in Korea. The genetic diversity and population differentiation in the two remnant populations of the species were investigated using RAPD (random amplified polymorphic DNA) analysis. The Neis gene diversities were 0.146 in the smaller population of 45 individuals, and 0.151 in the larger population of 61 individuals. The genetic variation was not significantly different between these two populations. Genetic diversity within populations was not low considering the very small size of populations. Analysis of molecular variance (AMOVA) revealed higher variation within populations (65.9%) than genetic differentiation between them (34.1%). B. latissimum revealed higher population differentiation than other outbreeding species. The differentiation of the populations corresponded to low gene flow (Nem = 0.482). The cluster and principal coordination analyses provide strong support for high population differentiation, showing that all individuals of the two populations have built up population-specific clusters. Although gene flow between the two populations of B. latissimum was limited, they have preserved relatively high levels of genetic variation.