• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.9
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• pp.523-526
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• 2016

This paper was researched about 1,200 V level floating island IGBT (insulated gate bipolar transistor). Presently, 1,200 V level IGBT is used in Inverter for distributed power generation. We analyzed and compared electrical charateristics of the proposed floating island IGBT and conventional IGBT. For analyzing and comparison, we used T-CAD tool and simulated the electrical charateristics of the devices. And we extracted optimal design and process parameter of the devices. As a result of experiments, we obtained 1,456 V and 1,459 V of breakdown voltages, respectively. And we obatined 4.06 V and 4.09 V of threshold voltages, respectively. On the other hand, on-state voltage drop of floating island IGBT was 3.75 V. but on-state vlotage drop of the conventional IGBT was 4.65 V. Therefore, we almost knew that the proposed floating island IGBT was superior than the conventional IGBT in terms of power dissipation.

• Journal of the korean society of oceanography
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• v.38 no.2
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• pp.45-51
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• 2003

Recent observations reveal that the Tsushima Current has a double-cored structure downstream of the Tsushima Island. To explain this, a simple analytical model is proposed based on the assumption of small lateral eddy viscosity. This model suggests that an otherwise uniform current becomes to have a stream core immediately after it enters a channel due to the action of lateral friction. The core is initially broad but becomes sharper downstream. The speed at which the core develops depends on the intensity of lateral eddy viscosity. Likewise, a single-cored stream changes rapidly to a double-cored stream when it passes through an island located in the center of the channel. When the stream leaves the island behind, the reverse process from the double-to single-cored structures takes place. In this case, however, the double-cored structure is retained for a significant distance from the island. Overall, this model suggests that the double-cored structure of the Tsushima Current observed downstream of the Tsushima Island Is created by the lateral friction exerted by the Tsushima Island.

• Journal of the Korean Solar Energy Society
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• v.36 no.3
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• pp.45-52
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• 2016

Remarkable air temperature increases in urban areas are known as heat island phenomenon. In this study, we analyzed the effects of renewable energy on the heat island phenomenon in urban area by numerical method. The results showed that the use of renewable energy reduces the building energy use in urban area and contributes the alleviation of the Urban Heat Island Effects.

• Animal Systematics, Evolution and Diversity
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• v.14 no.3
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• pp.207-217
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• 1998

Twenty nin species of marine bryozoans are reported from Geojedo Island, Korea. Of these, two species, Chaperia acanthina and Antropora tincta are new to Korea fauna, Only two species, Amathia distans and Tricellaria occidentails, included in this paper, were previously recorded from Geojedo Island. Therefore twenty five species of marine bryozoans is newly recorded from Geojedo Island.

• Journal of Ecology and Environment
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• v.32 no.2
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• pp.129-135
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• 2009

We investigated the moth diversity on an island of southern sea of Korea. We collected moths at three sites on the island of Bogildo, Wando-gun, Jeonnam using a 22-watt ultraviolet light trap from May to October, 2008, and identified a total of 272 species and 948 individuals in 13 families. Species of Noctuidae was the most abundant, with 107 species and 318 individuals, followed by Geometridae (62 species and 147 individuals) and Pyralidae (53 species and 269 individuals). The graph of the estimated species richness in Chao 1 (432.25$\pm$37.39) did not reach an asymptote, which suggests that more moth species could be identified on the island through further sampling. An arctiid moth, Miltochrista striata, was the most abundant species captured in this study. Monthly changes in moth species richness and abundance formed M-shaped curves, with peaks in early summer (June) and late summer (August). Cluster analysis of seven sites on three islands (Aphaedo Island, Sinan-gun, Oenarodo Island, Goheung-gun and Bogildo Island) divided the sites into two groups. Distances among sites and habitat types may play an important role in determining the similarities of moth faunas among sites.

• Korean Journal of Environment and Ecology
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• v.11 no.3
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• pp.352-365
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• 1997

As a serials of researches for the restoration model of evergreen broad-leaved forests, the restoration strategies of the case study areas were proposed. Restoration type of vegetation were classified into an improvement type and a reconstruction type and a reconstruction type for Wando(Island). Improvement type of restoration was suggested for Mokdo(Island). Quercus acuta community, Q. salicina community, Neolitsea sericea community, Castanopsis cuspidata var. sieboldii community, Machilus thunbergii community, Cinnamomum japonicum community, etc. were suggested as a restoration goal of vegetation for Sando(Island). Machlus thunvergii community was suggested as a restoration goal of vegetation for Mokdo(Island). Also the species restoration olan of the Wando(Island) was prepared for Quercus salicina of Fagaceae and Ostrya japonica of Betulaceae those which the natural distribution and population size were very limited. There was no species which needed for species restoration urgently at Mokdo(Island).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.2
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• pp.148-158
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• 2004

In the adjacent seas of Cheju Island, the oceanographic conditions show low salinity surface waters starting in May. This water flows from the southeast part of the China Coastal Water, which flows southeastward along the Great Yangtze Sand Bank until April, with the help of southeasterly winds and flows from the adjacent sea off Cheju Island. In May, the Tsushima Warm Current and the low salinity surface water fluctuate in short and long-term periods as influenced by Yellow Sea Cold Water, which flows to the bottom layer at the western entrance of Cheju Strait. Temperature and salinity fronts in the northeastern sea area of U Island are formed in the boundary area between the Tsushima Warm Current, which expands towards Cheju Island from the southeastern sea area of Cheju Island and Hows out from the eastern entrance of the strait. Seasonally, additional oceanographic conditions, such as coastal counter-currents, which flow southward, appears within limited areas in the adjacent eastern and western seas of Cheju Island.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.23
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• pp.10091-10094
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• 2015

Easter Island is a small island of $180km^2$, located 3,800 km from the Chilean coast and one of the most isolated inhabited places in the world. Since the mid-twentieth century, it has been undergoing an epidemiological transition in relation to the causes of death, from a predominance of infectious to non-communicable diseases (NCDs) such as cardiovascular ailments and cancer. The aim of this study is to describe the causes of death to Easter Island between 2000 and 2012, so the statistical records of Hanga Roa Hospital and death certificates were reviewed. The period under review of 13 years there was a total of 252 deaths, an average to 19.3 deaths per year. The most frequent causes of death found in the general population of Easter Island were cardiovascular diseases (25.4%), followed by neoplasms (23.4%), accidents (18.6%). Related to Rapa Nui people, cardiovascular and neoplastic diseases (both 26.7%) predominate, while in the population without belonging to the ethnic group the main causes were traumatic (25%) and cardiovascular (22.2%). Comparing the leading causes of death of Easter Island with mainland Chile, it can be seen how they resemble. Taking the island death profile, it is necessary to work on public health strategies aimed to this, considering that some of the causes are completely preventable.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.6
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• pp.635-641
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• 1998

Two months old Fayoumi, Rhode Island Red, and Fayoumi ${\times}$ Rhode Island Red chickens were reared upto 512 days of their age in the villages surrounding Bangladesh Agricultural University in order to study comparative performances of the 3 genetic groups with or without extra feeding to scavenging system of rearing and also, to study the suitability of these breeds reared under the rural condition. Fayoumi attained earlier sexual maturity (238.5 vs 262.5 d) and laid more eggs than other breeds/types. Rhode Island Red produced the largest eggs, but mortality rates were highest and Fayoumi showed greatest resistance to diseases. Crossbred was heaviest (1,275 g at 247.5 d of age) and had highest hatchability than parental breeds. Age at sexual maturity (247.5 d), 50% egg production, peak production and mortality in crossbreds were mostly influenced by sire Fayoumi but for the egg weight and body weight, the effect of the dam Rhode Island Red was significant. Extra feeding was found more beneficial to the chickens irrespective of breeds and types. The crossbred Fo ${\times}$ RIR chickens were found more suitable under rural scavenging system than the exotic breeds, Fayoumi and Rhode Island Red in the rural areas of Bangladesh.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.3
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• pp.74-82
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• 1999

This study is aimed to establish the development plannings for the sustainable tourism of Yongyoo Island and Mooeui Island, neighboring areas of Youngjong Island, for the conservation and environmentally friendly use of Korean coastal wetlands. The concepts of sustainable tourism is described. The current development status and its problems of Youngjong Island and its neighboring areas are analysed. The development plannings for sustainable tourism of Yongyoo Island and Mooeui Island are suggested as follows : (1) The small scale tourism development projects, which are able to represent region's own characteristics, instead of large scale ones, should be performed. (2) The participation of community people should be guaranteed at the beginning stage of the decision making processes for tourism development projects. Additionally, the profits of the development should be fairly distributed among community people. (3) The coastal wetlands should be conserved and their sewage disposal capacity should be protected by way of the minimization of reclamation. (4) The coastal wetlands should be developed into the tourist resorts utilizing migratory birds as tourism resources. In addition, the carrying capacity of the coastal wetlands, which is based on the current status of ecosystems and the Environmental Impact Assessment(EIA), should be calculated.