• Journal of the Korean earth science society
• /
• v.24 no.4
• /
• pp.337-345
• /
• 2003

Surficial sediments from the northern coastal area of Jeju Island, southeastern Yellow Sea (South Sea of Korea) were analyzed for grain-size texture, some geochemical characteristics and clay mineralogy in order to assess their provenance. Rare-earth element compositions and some geochemical discrimination diagrams, especially of Ti/Al, Nb/Al and Rb/Al ratios, were revealed to be useful indices for identifying the origin of sediments. These indices, together with clay mineral compositions, suggest that the coarse-grained sediments originate from the volcanic rocks of Jeju Island, whereas the fine-grained sediments are derived from Chinese rivers, especially the Changjiang River. The oceanic circulation pattern and the physical-chemical properties of seawater in the Yellow and East China seal support the possibility that the fine-pained Changjiang (Yangtze River) sediments can reach the coastal area of Jeju Island (southeastern Yellow Sea).

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.50 no.3
• /
• pp.385-395
• /
• 2014

This study is one of the research series for providing basic data that would contribute to the development of the field of fishing industry through the systematic fishing management, protection of fishery resources and healthy fishing culture with safety measures for fishermen in Jeju island according to the implementation of "Fishing Management and Support Act". As a result of analyzing the related acts, the contents of this study are related with provisions of "Fishing management and Support Act" on acts on fishing management, fish bait management, support for fishing and fishing related industries and with provisions of "Act of the preservation and management of desert island" on the preservation, use and development of desert island (use and development in a desert island, behavior in usable desert island). As a result of the survey, the rocks on the seashore showed the highest popularity with 52.6% for fishermen and the seawall was the highest with 47.1% for Maritime police as their fishing place in the fishing related activity data. And as the survey result about the awareness of "Fishing management and Support Act", 65.2% of general fishermen, 36.0% of maritime police and 70.5% of fishing related agencies answered that they knew the act. It was also surveyed whether they consider its contribution to fishing related industry development and positive result was shown by general fishermen and maritime police with 46.8%, 48.0% respectively whereas fishing-related enterprises showed negative answer with 47.7%. In the survey of fishing related regulation standard, general fishermen, maritime police and fishing related agencies all showed different opinions regarding the regulation standard. It is recommended that regulation standard needs to be set up after detailed review.

• Proceedings of KOSOMES biannual meeting
• /
• 2008.05a
• /
• pp.177-180
• /
• 2008

Based on Latti(1974) and Jacobs&Way(1968)'s theory, we estimate the coastal area of Jeju and Busan cities. According to the estimateio, The seawater pumping line causes the problem of coastal landscape. Water management treatment of coastal region has been an important problem in Jeju city and Busan city since the distributions of pipeline if the pumping system made a bad view in coastal region. To solve the problem, we observed the pipelines that are on the surface around the coastal region we proposed two methods, that is, one is a short time treatment, the other is a long time one. The short is based on the colour treatment, which is pipeline colour changing into surround natural one. The long time is the construction plan design method. Although the later method was very useful in Jeju island. However, it takes a lot of time and money. Therefore, in the situation, the short time is the better than the long time one.

• Archives of Craniofacial Surgery
• /
• v.21 no.6
• /
• pp.357-362
• /
• 2020

Background: Full-thickness skin grafts (FTSGs) have been widely used after facial skin cancer resection, for correcting defects that are too wide to be reconstructed using a local flap or if structural deformation is expected. The preauricular, posterior auricular, supraclavicular, conchal bowl, nasolabial fold, and upper eyelid skin areas are known as the main donor sites for facial FTSG. Herein, we aimed to describe the effectiveness of using infraclavicular skin as the donor site for specific cases. Methods: We performed FTSG using the infraclavicular skin as the donor site in older Asian adults following skin cancer resection. Outcomes were observed for > 6 months postoperatively. The Manchester Scar Scale was used for an objective evaluation of satisfaction following surgery and scarring. Results: We analyzed the data of 17 patients. During follow-up, the donor and recipient sites of all patients healed without complications. Upon evaluation, the average Manchester Scar Scale scores for the recipient and donor sites were 7.4 points and 5.7 points, respectively. Conclusion: In general, conventional donor sites, such as the preauricular, posterior auricular, and supraclavicular sites, are widely used for facial FTSG because they achieve good cosmetic results. However, the infraclavicular skin may be a useful donor for facial FTSG in cases where the duration of time spent under anesthesia must be minimized due to a patient's advanced age or underlying health conditions, or when the recipient site is relatively thick area, such as the nose, forehead, or cheek.

• Ocean and Polar Research
• /
• v.44 no.2
• /
• pp.113-126
• /
• 2022

This study was carried out to investigate the benthic polychaetous community and benthic ecosystem quality status on the adjacent continental shelf of Jeju Island, and field surveys were conducted at 31 stations in July and August, 2020. The surface sediment was generally composed of muddy sand facies and sandy mud facies, and the average particle size was medium silt (6.1±1.6∅). The benthic polychaetous community revealed a total of 73 species with a mean density of 242 ind./m². The major dominant species were Notomastus latericeus, Ampharete arctica and Onuphis shirikishinaiensis. By the cluster analysis and nMDS results based on species composition of the benthic polychaetous community, the study area was divided into three station groups arranged from east to west by the water depth and sedimentary facies. The station group located in the west was subdivided into two station groups from south to north. From results of correlation analysis and PCA, it was found that the benthic polychaetous community in the study area had a strong correlation with the sedimentary environment and water depth. The benthic faunal community (or ecosystem) on the adjacent continental shelf of Jeju Island was assessed to be in a healthy state by biotic indices such as AMBI and BPI.

• Journal of Environmental Science International
• /
• v.31 no.9
• /
• pp.735-741
• /
• 2022

Global warming affects forests and their ecology. Diversity in the forest is a buffer that reduces the damage due to global warming. Mixed forests are ecologically more valuable as versatile habitats and are effective in preventing landslides. In Korea, most forests were created by simple afforestation with trees of evergreen species. Typically, evergreen trees are shallow-rooted, and deciduous trees are deep-rooted. Mixed forest tree roots grip the soil effectively, which reduces the occurrence of landslides. Therefore, improving the distribution of tree types is essential to reduce damage due to global warming. For this improvement, the investigation of tree types of the forest is needed. However, determining the tree type distribution of forests that are spread over wide areas is labor-intensive and time-consuming. This study suggests effective methods for determining the distribution of tree types in a forest that is spread across a relatively wide area. Using normalized difference vegetation index and RGB images from unmanned aerial vehicles, each evergreen and deciduous tree, and grassland area can be distinguished. The distinguished image determines the distribution of tree type. This method is effective compared to directly determining the tree type distribution in the forest by the use of manpower. The data from these methods could be applied to plan a mixed forest or to prepare for future damage due to global warming.

• Journal of the Korean Applied Science and Technology
• /
• v.40 no.1
• /
• pp.71-80
• /
• 2023

Silver paste is a valuable electrode material for electronic device applications because it is easy to handle with relatively low heat treatment. This study treated the electrode surface using an atmospheric-pressure plasma jet on the silver-paste electrode. This plasma jet was generated in an argon atmosphere using a high voltage of 5.5 to 6.5 kV with an operating frequency of 11.5 kHz. Plasma-jet may be more beneficial to the printing process by performing it at atmospheric pressure. The electrode surface becomes hydrophilic quickly and contact angle variation is observed on the electrode surface as a function of plasma treatment time, applied voltage, and gas flow rate. Also, there was no deviation in the contact angle after the plasma treatment in the large-area sample, that means a uniform result could be obtained regardless of the substrate size. The outcomes of this study are expected to be very useful in forming a stacked structure in the manufacture of large-area electronic devices and future applications.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2022.01a
• /
• pp.159-162
• /
• 2022

담낭용종의 잘 알려진 위험요소는 대사증후군, 연령, 이상지질혈증 등이다. 제주도는 한반도에서 가장 큰 섬으로 한국의 본토에서 약 80km 떨어져 있으며 행정구역상 제주시와 서귀포시로 나뉘어 있지만 기업들과 편의시설들, 학교들 때문에 자연스럽게 시내와 시외로 더 나누어진다. 많은 이주민들과 젊은 성인들은 상업 활동이 활발한 시내 지역에 사는 경향이 있다. 고령 성인들은 어업이나 농업에 종사하기 때문에 시외 지역에 사는 경향이 있다. 고령의 성인들은 전통적인 식이를 유지하고 있고, 그들 중 다수는 힘든 노동으로 인해서 고위험 알코올 음주자의 비율이 높다. 이러한 요인들로 인해 두 지역간의 담낭용종 유병률에도 차이가 있을 것이다. 따라서 이 연구의 목적은 제주도 두 지역간에 담낭용종의 유병률을 알아보고 그 유병률과 관련된 다양한 요인들을 비교해 보고자 하는 것이다. 이 연구는 2009년 1월부터 2019년 12월까지 제주대학교병원 단일 건강검진센터에서 건강검진을 시행한 21,734명을 대상으로 하였다. 시내 지역과 시외 지역 거주민들의 담낭용종 유병률은 각각 10.1%와 8,7% (P = 0.006)로 의미있게 차이가 있었다. 평균 총콜레스테롤 수치가 시내 지역 거주민들에서 시외 지역 거주민들보다 높았고, 음주와 관련된 평균 알카라인 인산분해효소와 감마-글루타밀전이효소 수치들과 평균연령은 시외 지역 거주민들이 시내 지역 거주민들보다 더 높았다. 나이, 알코올 섭취와 평균 콜레스테롤 수치가 이러한 두 지역 간에 담낭용종 유병률의 차이를 만들었을 것이다.

• Proceedings of the Korea Society of Environmental Biology Conference
• /
• 2006.06a
• /
• pp.9-10
• /
• 2006

• Analytical Science and Technology
• /
• v.29 no.1
• /
• pp.19-28
• /
• 2016

The objective of this study was to determine the acidification of precipitation in the Jeju area. Precipitation samples were collected from the Jeju area from 2009-2014, and the major ionic species were analyzed. In the regression analysis, through a comparison of ion balance, electric conductivity, and acid fraction, the correlation coefficients showed a good linear relationship within the range of 0.927~0.983. The volume-weighted means of the pH and electric conductivity were 4.9 and 22.7 µS/cm, respectively. The ionic strength of precipitation was 0.27±0.38 mM, indicating about 35.9 % of total precipitation within the pure precipitation criteria. The volume-weighted mean concentrations (ìeq/L) of the ionic species in the precipitation were in the order of Na⁺ > Cl⁻ > nss-SO₄²⁻ > NO₃⁻ > NH₄⁺ > Mg²⁺ > H⁺ > nss-Ca²⁺ > PO₄³⁻ > K⁺ > HCOO⁻ > CH₃COO⁻ > NO₂⁻ > F⁻ > HCO₃⁻ > CH₃SO₃⁻ . The acidification contributions by sulfuric and nitric acids were 54.5 % and 36.5 %, respectively. Meanwhile the acidification contributions by formic and acetic acids were 4.8 % and 4.2 %, respectively. Thus, it was found that the acidification of the precipitation in the Jeju area was mainly due to the inorganic acids. The neutralization factors by NH₃ and CaCO₃ were also 33 % and 20 %, respectively.