• Journal of the Korean association of regional geographers
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• v.21 no.2
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• pp.394-410
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• 2015

This study aims to classify climate zones for extreme climate indices over the Republic of Korea. First, frequencies and magitudes of extreme high temperature, spatial distributions for extreme low temperature, and extreme precipitation are analysed. Frequencies of summer days in inland region show more than coastal region. In frequencies of frost days, the characteristics of altitude and longitude are appeared. Heavy precipitation days show many frequencies in the southern coastal region and Jeju island, but little in Gyeongsangbuk-do region. The classification of climate zone for extreme climate indices by principal component analysis and cluster analysis is conducted for the first half, second half of study period, and climatology period for 1981-2010. Summer days are classified according to latitude. In case of frost days, the eastern and the southern coastal region and Jeju island are classified as same region. Heavy precipitation days are classified according to longitude in south region of Gyeonggi-do and Gangwon-do. This study will help to prepare adaptation and mitigation system for climate change in wide range of fields.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.814-824
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• 2020

Recently, public interest in air pollutants has increased, and the Korean government and local governments have attempted to improve air quality. This study examined the secondary air pollutant contribution in Ulleung Island, Jeju Island, and Baengnyeong Island and compared the differences between them by analyzing the air pollution level and weather conditions in these regions. The weather conditions of the island regions, such as wind speed, precipitation, and sunshine duration, and the average concentration of air pollutants, such as SO₂, NO₂, CO, O₃, PM₁₀, PM_2.5, were examined. The correlation coefficient between air quality factors of each island region and weather conditions was calculated. Regression analysis was conducted by setting primary air pollutants, SO₂, NO₂, and CO as independent variables, and secondary air pollutants, O₃, PM₁₀, and PM_2.5 as dependent variables to identify the regional contribution and impact. Therefore, the government and local governments should establish air quality management for each island region.

• Journal of Ecology and Environment
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• v.34 no.2
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• pp.137-147
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• 2011

In 2009, United Nations Educational, Scientific and Cultural Organization (UNESCO) recognized the unique outstanding ecosystem biodiversity and distinct ecocultural values of the Shinan Dadohae Biosphere Reserve in the island region. The Dadohae area, which has been sustainably conserved for scores of years, boasts not only a unique ecosystem, but also has residents with a wide range of traditional ecological knowledge. In terms of understanding the soundness of the ecosystem network known as the landscape system, the recent expansion of environmental development has served to heighten the degree of consideration given not only to biodiversity, which has long been used as an indicator to assess ecosystem soundness, but also to assess cultural diversity. Man has used the surrounding landscape and living organisms as his life resources since the beginning. Moreover, whenever necessary, man has developed new species through cultivation. Biodiversity became a foundation that facilitated establishing cultural diversity such as food and housing. Such ecological knowledge has been conveyed not only to adjacent regions, but also at the international level. The recent rapid changes in the Dadohae area island ecosystem caused by the transformation of fishing grounds by such factors as climate change, excess human activities, and marine pollution, is an epoch event in environmental history that shows that the balance between man and nature has become skewed. Furthermore, this issue has moved beyond the biodiversity and landscape diversity level to become an issue that should be addressed at the cultural diversity level. To this end, the time has come to pay close attention to this issue.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.561-566
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• 2017

Few studies on the finless porpoise Neophocaena asiaeorientalis have been conducted on the south coast of Korea. This region includes Gadeok Island, which is located off the Korean peninsula in an area of heavy maritime traffic. Sighting surveys of finless porpoises were conducted at seven predetermined spots around Gadeok Island in January, May, July, September, and November 2016. Finless porpoises (127 individuals in 24 schools) were sighted at all but one (spot P5) of the survey locations. Fewer porpoises were spotted in summer (Jul and Sep) than in other seasons (P<0.05). Porpoises were most abundant around the south coast of the island, where they were spotted in every season, and in significantly higher numbers than at other locations (P<0.05). Single individuals accounted for 20.8% of sightings, while 25.0% of sighted schools consisted of only two porpoises. The mean school size was 5.29 individuals (SD=6.72).

• Korean Journal of Health Education and Promotion
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• v.24 no.3
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• pp.87-98
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• 2007

Objectives: This study was aimed to observe health behaviors of middle school and high school students in an Island. Methods: A self-administered questionnaire survey was carried out for total 414 people(middle school 285-men 160 and women 125, high school 129-men 71 and women 58) who resident in Ulleung-do Gyeoungsang-Bukdo from 1th to 30th November, 2005. results: Test main characters of smokers were men(p<0.01), high school student(p<0.01), low school-score(p<0.01), unsatisfacted school lift(p<0.05), smoking of parents(p<0.01), long attending duration of school in Ulleung-do(p<0.01) and existence of mental effect by an island life(p<0.05), the answered. The more drinkers lived together parents(p<0.05), that their habits were effected by island life rather than non-drinkers.(p<0.05). Conclusion: Among the participants, health-related problems varied in the region. To account for these problems, educational programs or counselling services may be employed.

• 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.

• Archives of Reconstructive Microsurgery
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• v.7 no.1
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• pp.10-14
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• 1998

When covering a skin defect of the finger with a local flap is difficult, a vascular island flap is often used. For a palmar skin defect, it is desirable to add a sensory supply to the flap. This report describes a neurovascular island flap that was used to repair a palmar skin defect, the donor skin coming from the dorsal region of the middle phalanx. This flap is elevated with a vascular pedicle of the palmar digital artery and its dorsal skin branch, including the dorsal digital veins, palmar digital nerve and its cutaneous branches. The advantage of this flap are that it can be transferred with ease and without any tension. No special manipulation is required under a microscope and operation can be performed under a simple nerve-block. There if little possibility that the flap itself undergoes ischemic change or congestion. The disadvantage of this flap are that a skin graft is required at the donor skin site and one palmar digital aretery is lost. We think that this neurovascular island flap is one of the useful methods for skin defects that are difficult to cover with a local flap.

• Ocean and Polar Research
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• v.42 no.3
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• pp.211-223
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• 2020

With the increasing demand for improved marine environments and safety, greater ability to minimize damages to coastal areas from harmful organisms, ship accidents, oil spills, etc. is required. In this regard, an accurate assessment and understanding of current systems is a crucial step to improve forecasting ability. In this study, we examine spatial and temporal characteristics of current systems in the adjacent seas of Jeju Island using a high-resolution regional ocean circulation model. Our model successfully captures the features of tides and tidal currents observed around Jeju Island. The tide form number calculated from the model result ranges between 0.3 and 0.45 in the adjacent seas of Jeju Island, indicating that the dominant type of tides is a combination of diurnal and semidiurnal, but predominantly semidiurnal. The spatial pattern of tidal current ellipses show that the tidal currents oscillate in a northwest-southeast direction and the rotating direction is clockwise in the adjacent seas of Jeju Island and counterclockwise in the Jeju Strait. Compared to the mean kinetic energy, the contribution of tidal current energy prevails the most parts of the region, but largely decreases in the eastern seas of Jeju Island where the Tsushima Warm Current is dominant. In addition, a Lagrangian particle-tracking experiment conducted suggests that particle trajectories in tidal currents flowing along the coast may differ substantially from the mean current direction. Thus, improving our understanding of tidal currents is essential to forecast the transport of marine pollution and harmful organisms in the adjacent seas of Jeju Island.

• Economic and Environmental Geology
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• v.22 no.2
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• pp.141-150
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• 1989

In order to make economic and geological evaluation of coal in Korea, proximate and ultimate analyses were carried out as well as coal petrological studies such as maceral analyses, vitrinite reflectance and sporinite fluorescence measurement. The coeffcient of correlation between each factor of both conventional utilization and coal petrological parameters were studied as in Table 5 and 6. Their conclusions were as follow: (1) for anthracite, the good parameters of coal rank are mean vitrinite reflectance, carbon content, hydrogen content and H/C atomic ratio: (2) for brown coal and sub-bituminous coal, the good parameters of coal rank are carbon content, calorific value, moisture content, hydrogen content, oxygen content and O/C atomic ratio as well as vitrinite reflectance and sporinite fluorescence. An attempt is made to infer the coalforming environment by utilization of coal petrological analyses and to make comparison of coal analyses with proximate and ultimate analyses throughout the island arc region including Japan, Philippine and Indonesia and continental region including USA, Canada and Australia. As a result, meceral composition of Paleozoic and Mesozoic anthracite are similar to that of the Paleozoic continental coals, which were formed under dry conditions or low water table, but the coalification degree suddenly increased during Daebo orogeny (middle Jurassic to lower Cretaceous). The Tertiary coal resembles those of Tertiary island arc region coal characterized by higher calorific value, volatile matter content and H/C atomic ratio and by the formation of coal under wet conditions or higher water table.

• Asian Journal of Atmospheric Environment
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• v.10 no.2
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• pp.80-89
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• 2016

In the complex terrain where local wind systems are formed, accurate understanding of regional wind variability is required for wind resource assessment. In this paper, cluster analysis based on the similarity of time-series wind vector was applied to classify wind regions with similar wind characteristics and the meteorological validity of regionalization method was evaluated. Wind regions in Jeju Island and Busan were classified using the wind resource map of Korea created by a mesoscale numerical weather prediction modeling. The evaluation was performed by comparing wind speed, wind direction, and wind variability of each wind region. Wind characteristics, such as mean wind speed and prevailing wind direction, in the same wind region were similar and wind characteristics in different wind regions were meteor-statistically distinct. It was able to identify a singular wind region at the top area of Mt. Halla using the inconsistency of wind direction variability. Furthermore, it was found that the regionalization results correspond with the topographic features of Jeju Island and Busan, showing the validity.