• 한국수산과학회지
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• 제52권6호
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• pp.696-701
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• 2019

Five specimens (839 - 1280 mm TL, Total length) of the dusky shark Carcharhinus obscurus, belonging to the family Carcharhinidae, were collected from the waters off Jejudo Island, Sinan, Namhae, Busan and Gangneung, Korea, during 2010-2019. Carcharhinus obscurus was similar to Carcharhinus brachyurus but was distinguished by the interdorsal ridge (present in C. obscurus vs. absent in C. brachyurus) and the shape of upper jaw teeth (broad in C. obscurus vs. narrow in C. brachyurus). In addition, 479 base-pair sequences in the mitochondrial DNA cytochrome c oxidase subunit I (COI) of our two specimens corresponded to those of C. obscurus (genetic distance, 0.000-0.003), but clearly distinguished from those of the Korean C. brachyurus (genetic distance, 0.03). We adopted the Korean name "Heuk-sang-eo" for Carcharhinus obscurus, after Kim and Ryu (2017).

• 대한원격탐사학회지
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• 제27권3호
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• pp.225-234
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• 2011

This study proposes an inversion algorithm to extract the surface parameters, such as surface roughness and soil moisture contents, using multi-frequency SAR data. The study areas include the tidal flats of Jebu Island and the reclaimed lands of Hwaong district on the western coasts of the Korean peninsula. SAR data of three frequencies were accordingly calibrated to provide precise backscattering coefficients through absolute radiometric calibration. The root mean square (RMS) height and the correlation length, which can describe the surface roughness, were extracted from the backscattering coefficients using the inversion of the Integral Equation Method (IEM). The IEM model was appropriately modified to accommodate the environmental conditions of tidal flats. Volumetric soil moisture was also simultaneously extracted from the dielectric constant using the empirical model, which define the relations between volumetric soil moistures and dielectric constants. The results obtained from the proposed algorithm were verified with the in-situ measurements, and we confirmed that multi-frequency SAR observations combined with the surface scattering model for tidal flats can be used to quantitatively retrieve the geophysical surface parameters in tidal flats.

• 한국환경복원기술학회지
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• 제5권1호
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• pp.59-65
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• 2002

The community of common reed (Phragmites australis) is expanded by the development of new shoots from nodes of rhizomes and old shoots in natural environments. We developed the useful technique to construct reed mats of floating islands developed from shoot nodes of reeds for the purpose of the rapid stabilization of vegetation and the application of adapted plants with their specific environmental conditions. The vegetation development was compared in the floating islands planted with the different reed samples. The reed samples were consisted of four types : long shoot in the length of 100 cm (AG I), short shoot of 15 cm (AG II), long rhizome of 100 cm (BG I) and short rhizome of 15 cm (BG II). Shooting started earlier in BG I and BG II than in AG I and AG II. But the rate of shooting was higher in AG I and AG II than in BG I and BG II. After four weeks, AG I and AG II were higher than BG I and BG II in the biomass and density of newly developed shoots. These results showed that the construction of sod mats by planting only reed shoots was a useful technique to develop vegetation on the floating islands.

• 한국수산과학회지
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• 제44권6호
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• pp.677-683
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• 2011

Eleven individual larvae (3.6-8.0 mm notochord length, NL) were collected from the southern East Sea of Korea in July, 2010, and the adjacent Sea of Jeju Island in August, 2011. Five individuals were identified using mitochondrial DNA cytochrome oxidase subunit I (COI) sequences (494 base pairs). All were identified as Auxis rochei, their mtCOI sequences being consistent with those of adult A. rochei (d=0.000), followed by Auxis thazard (d=0.027). In terms of morphology, A. rochei larvae showed a preflexion stage of 4.8 mm NL, but a flexion stage between 5.2-6.2 mm NL, and subsequently a postflexion stage between 6.6-8.0 mm NL. During the larval stage, A. rochei differed from A. thazard in having no (or few) melanophores in the lateral caudal region.

• 식물분류학회지
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• 제40권4호
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• pp.251-254
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• 2010

제주도에서 발견된 사철란(난과)속의 신분류군을 정기준표본에 근거한 분류군 기재, 해부도 및 서식지에서의 식물사진을 제시하여 탐라사철란(Goodyera ${\times}$ tamnaensis N.S. Lee, K.S. Lee, S.H. Yeau & C.S. Lee, sp. nov.)으로 신종 처리하였다. 탐라사철란은 잎맥, 잎 표면무늬와 잎의 표피세포 형태, 잎, 꽃과 포의 색, 곁 꽃받침의 모양, 털의 길이 등 형태적 특징에 의해 사철란과 흰줄사철란(털사철란)의 교배종으로 추정된다.

• 한국어류학회지
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• 제31권4호
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• pp.249-254
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• 2019

여을멸과에 속하는 Albula sp. 1개체를 제주도 연안의 정치망에서 채집하여 형태적 특징을 기술하였다. 이 개체는 73개의 측선공과 72개의 척추골, 그리고 뺨에 무늬가 없는 특징으로 형태적으로 Albula argentea로 동정되었다. 보다 명확한 종 동정을 위해서 표본조직으로부터 미토콘드리아 사이토크롬 b 염기서열을 얻은 후 기존에 보고된 10종의 Albula spp.와 비교 분석한 결과, 분자생물학적으로도 A. argentea와 동일종으로 나타났다.

• Plant Resources
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• 제8권3호
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• pp.244-249
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• 2005

The growth charateristics and karyotypes of Aster spathulifolius collected from 5 sites including coastal and island region on the Korean peninsula, were analysed. Several morphological characteristics of the plants such as leaf length, leaf width, top internode, medium internode, spike branching, flower diameter, number of petal, leaf color, leaf form, stem and leaf hair, viscosity, and serration of the plants were distinctly different depending on the native region from which they were collected. Karyotypic analysis showed that the chromosome number was all diploid (2n=18), with one pair of submetacentric satellite chromosomes. The chromosome composition included 7 pairs of metacentric chromosomes and 2 pairs of submetacentric chromosomes in all plants. However, chromosome order and the ranges of the chromosome lengths were a little different from plant to plant according to their native growing regions. The plants from Geoje-Do especially showed large differences in the chromosome lengths between the longest and the shortest compared to the plants from other places. This results provide important data to support the classification of the species into several sub-species.

• 한국식생활문화학회지
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• 제30권6호
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• pp.778-782
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• 2015

Demand for organic agriculture has greatly increased in the past decade. The objective of this study was to evaluate quality the characteristics and antioxidant activities of organically and conventionally grown carrots. Organically and conventionally grown carrots were harvested in Jeju Island, Korea. Carrot extracts were investigated for their antioxidative components (total phenolic and flavonoid contents) and their antioxidant activities (DPPH and ABTS radical scavenging activities). The quality characteristics of carrots were estimated in terms of hardness, length, weight, moisture contents, and soluble solid content (SSC). Conventionally grown carrots showed higher values than organic carrot in terms of hardness (p<0.05), but there was no significant difference in moisture contents or SSC. In the case of antioxidant activity, organic carrots showed a higher value for DPPH radical scavenging activity (p<0.05). However, there was no significant difference in other antioxidants. Consequently, quality characteristics and antioxidant activities were different between organically and conventionally grown carrots.

• 한국수산과학회지
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• 제52권4호
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• pp.424-429
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• 2019

Two juvenile (9.48 and 10.11 mm in standard length) specimens of the lanternfish Notoscopelus japonicus, belonging to the family Myctophidae, were collected from the waters around Busan and Jeju Island in February 2017. This species is characterized by having melanophores along the dorsal side of the body and one photophore (PO5) in front of the pelvic fin. It is distinguished from Benthosema pterotum in having many melanophores on the dorsal side and a single photophore (PO5) on the trunk. N. japonicus is also distinguished from its congeneric N. resplendens and N. caudispinosus in having no melanophores at the base of the anal fin. Analyzing 521 base pairs of the 16S rRNA sequence, the specimens were identical to N. japonicus adults from Japan (K2P distance <0.004). This is the first record of N. japonicus in Korea, and we propose a new Korean name "Deung-jum-saet-bi-neul-chi" for this species.

• 한국전기전자재료학회논문지
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• 제32권4호
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• pp.263-266
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• 2019

In the Airport Railroad, the Yeongjong Bridge has a length of 4,420 m and connects Yeongjong Island with the mainland of Incheon City. The bridge is a two-level structure, consisting of a six-lane road at the upper level and a combination of a road and railroad at the lower level. The environmental conditions for the electric railway come mainly from the salt injury area and a heavy industry zone, and the maintenance cycles are determined differently depending on these conditions. This study analyzed the deterioration characteristics of long rod insulators produced with a movable ceramic bracket and polymer materials in the Yeongjong Bridge section of the Airport Railway operating in the salt injury area according to the material characteristics. Comparison of the corona measurements when the insulators were cleaned at the same time showed that the polymer insulator had a higher insulation performance than the ceramic insulator.