• Journal of Electrochemical Science and Technology
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• v.14 no.1
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• pp.21-30
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• 2023

This work presents a correlation between the behavior of formic acid oxidation (FAO) on various Bi-modified Pt(poly) disk electrodes and their morphologies observed on Bi-modified Pt(111) disk electrodes using electrochemical scanning tunneling microscopy (EC-STM) to understand the effects of Bi on Pt. To distinguish the FAO activities of Bi on Pt and plain Pt around Bi, additional Pt was intentionally deposited using two different routes: direct route and iodine route. In direct route, Pt was directly deposited on Bi islands and plain Pt sites around Bi islands, while in iodine route, Pt was exclusively deposited on Bi islands by protecting plain Pt sites with adsorbed iodine. Thus, a comparison of FAO performances on the two Bi-modified Pt electrodes with additional Pt (deposited in the different ways) disclosed a difference in FAO performances on plain Pt sites and Bi islands. When Bi coverage was ~0.04, the Bi deposits were scattered Bi islands enhancing FAO on Pt(poly). The additional Pt deposits using direct route increased FAO efficiency, while the ones using iodine route slightly decreased FAO current. The EC-STM observations indicated that Pt deposits around Bi islands, not on Bi islands, were responsible for the FAO current increase on Bi-modified Pt(poly). The FAO efficiency on Bi-modified Pt(poly) with a Bi coverage of ~0.25 increased by a factor of 2. However, the additional Pt deposits using the two Pt deposition routes notably decreased the FAO current. The dependency of FAO on Bi coverage was discussed in terms of electronic effect and ensemble effect.

• Archives of Craniofacial Surgery
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• v.10 no.1
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• pp.40-43
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• 2009

Purpose: Extensive midface defect following total maxillectomy with orbital exenteration and cheek skin resection should be three dimensionally reconstructed with a large flap that have a sufficient volume of tissue and multiple skin islands. We describe our transverse rectus abdominis myocutaneous(TRAM) free flap with three skin islands which was successfully used in this situation. Methods: A 58-year-old man was performed enbloc total maxillectomy including orbital contents and wide cheek skin because of invasive maxillary squamous cell carcinoma. He was immediately reconstructed with TRAM flap that was designed not vertical but transverse fashion for providing sufficient skin area. Also, deepithelialization procedure making for multiple skin islands was done in flap insetting period when appropriate modification according to the intraoperative situation was possible. Dead space was completely obliterated by bulky muscular tissue, and three skin islands were used for lining of lateral nasal wall, palatal surface, and cheek skin restoration. Results: Postoperative course was satisfying. Maintaining of proper ipsilateral nasal airway, loss of rhinolalia and oronasal regurgitation of food particles, and restoration of cheek contour were successfully obtained. Conclusion: We report clinical experience of threedimensional reconstruction using free TRAM flap after total maxillectomy with orbital exenteration.

• The Korean Journal of Mycology
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• v.44 no.1
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• pp.16-22
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• 2016

Five islands (Sinjindo, Mado, Daenanjido, Wonsando, and Sapsido) and the coastal area (Muchangpo) in Chungnam, Korea, were selected to determine the diversity of arbuscular mycorrhizal (AM) fungi. Soil-inhabiting AM fungi were isolated and identified on the basis of morphological characteristics and sequence analyses of 18s rDNA. The differences in the fungal community structures were compared among sites. As a result, 24 species of AM fungi were identified, of which two species of AM fungi, Acaulospora brasiliensis and Redeckera fulvum, were isolated for the first time in Korea. This study revealed that AM fungal spore abundance was low and the genus Acaulospora was dominant in most of the islands. AM fungal community structures in five Islands were highly similar. However, the coastal area, Muchangpo, had different AM fungal community structure from the islands.

• Korean Journal of Plant Resources
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• v.25 no.1
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• pp.105-122
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• 2012

This study was carried out to illuminate the flora of vascular plants of islands at Chungnam. This study was conducted from March to November, 2010. Based on the voucher, vascular plants of in investigated islands were 105 families 326 genera 454 species 4 subspecies 45 varieties 9 forms, totally 512 taxa. Korean endemic plants were 6 species such as Aster koraiensis, Salix koriyanagi, Indigofera koreana, Hemerocallis taeanensis, Hepatica insularis, Philadelphus schrenckii, rare and endangered plants of designated by Korea Forest Service were 4 taxa, such as Magnolia kobus (planted), Koelreuteria paniculata, Berchemia racemosa var. magna, Glehnia littoralis respectively. Phytogeographical special plants were totally 69 taxa, which were grade I of 50 taxa, grade II of 1 axon, grade III of 11 taxa, grade IV of 4 taxa, and grade V of 3 taxa. 14 southern plants and 4 northern plant by criterion from climate change study were found in this area. Naturalized plants were 17 families 46 taxa, that was 9.1% of total vascular plants in this area. Even naturalized plants has not influence on the islands vegetation. However, regular passenger ferry between islands and increasing of visiter will be affecting vegetation.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.3 no.1
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• pp.23-31
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• 2022

The analysis of seven islands in Gogunsan archipelago, Korea with insect fauna and vascular plant flora was carried out based on a field survey conducted in May, July, and September. As a result, a total of 2,817 insect individuals including 264 species and 315 taxa of vascular plant were recorded. Bangchukdo the largest island among the seven islands showed the largest number both insect species and plant taxa. The similarity analysis suggested that the nearness of each island strongly affected the insect fauna and vascular plant flora on each island. In addition, there was significant correlation between the areas of each island and the numbers of insect species (Spearman's correlation coefficient=0.857, P-value=0.014). In the future, the results of this study can be used as data related to island ecology and conservation.

• Maritime Security
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• v.3 no.1
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• pp.211-235
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• 2021

As a result of the Falkland Islands War from April 2 to June 14, 1982, Britain overcame severe economic depression and reclaimed the glory of the former British Empire by winning the war. On the other hand, Argentina was greatly affected by the collapse of a military dictatorship and the birth of a democratic government. This study suggests strategies for responding to maritime disputes that may occur in Dokdo Island in the future by applying "DIME on PMESII" to the Falkland Islands dispute. In particular, the study analyzes how DIME (diplomacy, information, military, and economy) capabilities have an effect as a means of the total national power of a country that effectively controls the disputed territory. Based on the results of this study, the response strategies related to the Dokdo maritime dispute are as follows. First, effective control over the disputed territory should be effectively maintained and strengthened like in Britain. This strategy inspires patriotism, supports the government during warfare, secures a just cause for war, and gains international support. Second, 'DIME on PMESII' was effective in modern warfare by focusing our DIME capabilities on the weaknesses of the other country's PMESII system. That is, wars are not won simply by the conflict of armed forces but by a nation's overall national strength, such as diplomatic, information, and economic capabilities. Third, appropriate strategies for neighboring countries are needed to overcome the possibility of limited warfare in the sea through preparations for Dokdo maritime disputes in the future.

• Journal of agricultural medicine and community health
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• v.29 no.1
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• pp.195-206
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• 2004

Objectives: This study was conducted to investigate the patterns of medical utilization and factors affecting medical utilization of population living in islands of province of ChungCheongNam-Do. Methods: Demographic and socioeconomic state, medical utilization of 447 persons were surveyed from Sept. 9th to Sept. 18th, 2002. Results: In elder age group and lower educational group, the rate of medical utilization was high. As subjective health states get lower, the group used medical institution more(p<0.05). The group having more number of chronic diseases showed more medical utilization. And the group who needs 2 to 3 hours to reach to the medical institution showed high medical utilization(p<0.05). The factors having negative effect on using medical institution were economic concern and lack of proper clinic in the neighborhood. Conclusions: The lower economic level and the insufficiency of medical facilities on islands affect the utilization rate negatively. More accessible and effective medical systems for these population are expected.

• ALGAE
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• v.28 no.1
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• pp.53-62
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• 2013

Actinotrichia is a calcified galaxauracean red algal genus with temperate and tropical distributions in the Indian and Pacific Oceans. Morphological characteristics, along with rbcL and cox1 sequences, were analyzed from specimens collected in the western Pacific and the Indian Oceans. Both rbcL and cox1 data confirmed the occurrence of A. fragilis, A. robusta, and Actinotrichia sp. in this region. The presence of A. fragilis was verified in tropical Indo-Pacific and temperate northeast Asian waters and was characterized by high genetic diversity. Although A. robusta commonly occurs in the East China Sea, we confirmed its presence on rocks and crustose algae in the subtidal zone of three islands in the Andaman Sea. Actinotrichia sp. was similar to A. calcea in morphology and distribution, but with sufficiently different sequences, thus, additional sampling over the range will enable a more realistic evaluation of its taxonomic status.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.694-696
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• 2002

Growth behaviors of carbon nanotubes (CNTs) are studied in terms of catalyst by using scanning electron microscopy and transmission electron microscope (TEM). Catalyst films deposited on various substrates are agglomerated into nano-islands during the heat-up to the growth temperature. In particular, we focus on the direct investigation of the microstructures of the CNTs and the interface of CNTs-catalyst-substrate using cross-sectional TEM. We investigate relationship to the subsequent CNTs growth on each nucleation site. The growth of CNTs depends on the catalyst itself but not the silicide formation between the catalyst and the substrate.

• Korean Journal of Materials Research
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• v.23 no.1
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• pp.47-52
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• 2013

Graphene has been synthesized on 100- and 300-nm-thick Ni/$SiO_2$/Si substrates with $CH_4$ gas (1 SCCM) diluted in mixed gases of 10% $H_2$ and 90% Ar (99 SCCM) at $900^{\circ}C$ by using inductively-coupled plasma chemical vapor deposition (ICP-CVD). The film morphology of 100-nm-thick Ni changed to islands on $SiO_2$/Si substrate after heat treatment at $900^{\circ}C$ for 2 min because of grain growth, whereas 300-nm-thick Ni still maintained a film morphology. Interestingly, suspended graphene was formed among Ni islands on 100-nm-thick Ni/$SiO_2$/Si substrate for the very short growth of 1 sec. In addition, the size of the graphene domains was much larger than that of Ni grains of 300-nm-thick Ni/$SiO_2$/Si substrate. These results suggest that graphene growth is strongly governed by the direct formation of graphene on the Ni surface due to reactive carbon radicals highly activated by ICP, rather than to well-known carbon precipitation from carbon-containing Ni. The D peak intensity of the Raman spectrum of graphene on 300-nm-thick Ni/$SiO_2$/Si was negligible, suggesting that high-quality graphene was formed. The 2D to G peak intensity ratio and the full-width at half maximum of the 2D peak were approximately 2.6 and $47cm^{-1}$, respectively. The several-layer graphene showed a low sheet resistance value of $718{\Omega}/sq$ and a high light transmittance of 87% at 550 nm.