• Title/Summary/Keyword: 인공섬

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Analysis of Factors That Cause Light Pollution in Islands in Dadohaehaesang National Park (다도해해상국립공원 내 섬 지역의 빛공해 유발 요인 분석)

  • Sung, Chan Yong
    • Korean Journal of Environment and Ecology
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    • v.36 no.4
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    • pp.433-441
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    • 2022
  • Light pollution is one of the factors that disturb coastal and island ecosystems. This study examined the factors causing light pollution in the islands in Daedohaehaesang National Park using nighttime satellite images. This study selected 101 islands with an area of 100,000 m2 or more in Daedohaehaesang National Park, and measured the levels of light pollution of the selected islands by calculating mean nighttime radiance recorded in VIIRS DNB monthly images for January, April, August, and October 2019. Of seven districts of the park, The highest mean nighttime radiance was recorded in Geumodo district (17,666nW/m2/sr), followed by Geonumdo·Baekdo, Narodo, Soando·Cheongsando districts. By season, mean nighttime radiance in October was the highest at 9,509nW/m2/sr, followed by August, January, and April. Regression analyses show that the total floor area and the number of lighthouses in a 5 km buffer area had a statistically significant effect on mean nighttime radiance at all times, but those within the island did not, indicating that light pollution in islands in a national park where land development is strictly restricted is influenced by artificial lights in nearby areas. However, the total floor area of an island significantly affected mean nighttime radiance only in August, which appears to be attributed to the impact of intensive use of artificial light by visitors during summer vacation. The size of an island had a negative (-) effect on nighttime radiance. This negative effect suggests that light pollution is a type of ecological edge effect, i.e., the smaller island is more likely to have a relatively larger proportion of edge area that is affected by light emitted from the neighboring areas. The results of this study indicate that managing artificial lights in nearby areas is necessary to mitigate light pollution in islands in marine and coastal national parks.

A study on the characteristics for temporary ventilation of long subsea tunnels - focused on the current situation and improvement requirements (초장대 해저터널의 공사중 환기 특성에 관한 기초연구 - 현황 및 개선필요사항 중심)

  • Jo, Hyeong-Je;Chun, Kyu-Myung;Kim, Jong-Won;Lee, Ju-Kyung
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.17 no.2
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    • pp.153-166
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    • 2015
  • Long subsea tunnel to be built below the seabed, as compared to the general railway tunnel, is subject to many restrictions in terms of spatial limitation when vertical or inclined shafts are built for the purpose of ventilation and fire safety. So, the construction of some artificial island is required to provide ventilation. But, because of construction difficulty and cost increase, it is necessary to minimize the artificial island construction. The longer ventilation distance is, the more fresh air requirement is needed. When supply airflow becomes excessive, duct size is restricted by the limitations of structure clearance and fan pressure and power increase exponentially. Therefore, in order to build a long subsea tunnel, it is necessary to overcome these practical problems and to develop technical solution that can keep the comfortable condition of tunnel environment during construction. In this study, as on ventilation method development suitable for long subsea tunnel, through comparison of temporary ventilation capacity calculation methods during construction phase, domestic and abroad, the application of Swiss SIA 196 code is found suitable for long subsea tunnel. And, through experiment on leakage of the duct connector, we confirmed that the leakage ratio per 100 m of domestic duct connection type is between 1.5~3.0%. Based on S-class duct of SIA 196 code, ventilation distance is 10.2 km, So, ventilation distance can be longer if duct connection method is improved. So, we confirmed that the improvement of leakage ratio is key issue in the construction-phase ventilation of long subsea tunnel.

A Study on the Coastal Development Model Due to the Construction of Artificial Island (인공섬건설에 따른 해안선변형모델에 관한 연구)

  • 오세욱;민병형;김기철;김재중
    • Journal of Ocean Engineering and Technology
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    • v.6 no.2
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    • pp.133-142
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    • 1992
  • Beach evolution is of the most important problem is the coastal engineering. Especially, the structure construction through reclamation in the shallow water region nesar the beach will cause many severe problems around the structure. Beach evolution due to the construction of an artificial island in this study was studied using wave transform model and associated of an artificial island in this study was studied using wave transform model and associated sediment transport model. Numerical simulation of the model was applied to the Kwangan beach using the data of waves and shoreline of the area. The combined wave transform model and beach evolution model showed good results. The results show a breakwater will be needed to prevent severe erosion near the eastward Kwangan beach when construction an artificial island in the Suyong Bay. Good results of the study also suggest that the present model can be more widely applied to the prediction of beach evolution.

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해상신도시 건설에 따른 해수유동 수치모델링

  • 강석구;염기대
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 1992.08a
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    • pp.20-20
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    • 1992
  • 부산 해상신도시 건설과 관련하여 해수유동 체계 변화를 예측하기 위한 연구가 지난 1989년 이후 수행된 바 있다. 본 발표에서는 1991-1992년에 걸쳐 수행된 "인공섬 주변 정밀 해수유동 예측(수치실험)" 연구사업 수행결과를 간략히 소개한다.(중략)

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GEOTECHNICAL PROBLEMS OF ARTIFICIAL ISLANDS (인공섬의 토질공학적 문제점 고찰)

  • 안상로;엄용섭
    • Proceedings of the Korean Geotechical Society Conference
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    • 1992.10a
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    • pp.95-106
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    • 1992
  • The paper presents general engineering properties of soft marine sediments and related geotechnical problems associated with construction of artificial islands. Both of the data from foreing and domestic sources are utilized. The selection of soil improvement methods are also discussed.

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천연가스 탱크기초 강관파일의 전기방식

  • 이수홍;최윤식
    • 전기의세계
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    • v.44 no.4
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    • pp.31-41
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    • 1995
  • 본 논문에서는 바다 한가운데를 매립하여 만든 인공섬 위에 부식영향에 취약한 지역에 나관상태로 매설되는 액화 천연가스 탱크기초 강관파일에 전기방식을 적용하는 사례를 통하여 전기방식관련 자료검토와 현장예비조사를 통한 적정한 전기방식설계 적용, 전기방식 전위측정 시험방법, 방식설비 주위시설물에 대한 간섭영향등을 논술하였다.

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A study on the development and performance evaluation of duct coupling for the minimized leakage of temporary ventilation duct (공사 중 환기덕트 누풍 최소화를 위한 접속부 개발 및 성능평가 연구)

  • Jo, Hyeong-Je;Jun, Kyu-Myung;Min, Dea-Kee;Kim, Jong-Won;Beak, Jong-Hoon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.20 no.1
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    • pp.145-160
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    • 2018
  • Long subsea tunnel is subject to many restrictions in terms of spatial limitation when vertical or inclined shafts are built for tunnel ventilation. So, the construction of some artificial island is required to provide ventilation. But, because of construction difficulty and cost increase, it is necessary to minimize the artificial island construction. As a result, ventilation distance become longer and supply airflow becomes excessive due to air leakage, So, duct mounting for temporary ventilation is impossible or fan pressure and power increase exponentially. Therefore, in order to build a long subsea tunnel, it is necessary to overcome these practical problems and to develop technical solution that can keep the comfortable condition of tunnel environment during construction. In previous study, we have found that air leakage is the key factor in solving these problems and experimental results show that the new connection method has a leakage rate of about $1.46mm^2/m^2$ (Jo et al., 2017). In this study, we present the experimental results of the measurement of the leakage rate of the prototype with the new connection method, and analyze experimentally the improvement of the leakage rate when applying the flexible cover inside the duct to improve the leakage performance of the existing connection method.

21세기에 산다 - 꿈같은 주거공간

  • Korean Federation of Science and Technology Societies
    • The Science & Technology
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    • v.32 no.3 s.358
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    • pp.18-19
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    • 1999
  • 내일의 주거공간은 어떻게 달라질 것인가. 21세기는 해양을 끼고 새로운 생태도시가 건설되고 또 본격적인 해양개발시대를 맞아 5대양을 누비는 해상도시가 건설될 것이다. 인구 50만명이 상주하게 될 생태도시는 높이 5백m의 원형타워형 건물로 지상 1백25층, 지하 45층으로 지상은 식물생산공장, 지하는 50만명의 거주공간으로 모든 것을 자급하고 공해없는 미래형 도시를 이룰 것으로 본다. 또 세계 최초의 떠있는 해상도시는 상주인구 4만5천명 등 9만5천명을 수용하는 움직이는 인공섬으로 미국에서 10년 전부터 구상하고 있어 21세기에는 실현되어 5대양을 누비게 될 것이다.

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Outline of pusan Man-made Island & Consideration of Geotechnical Engineering (부산 인공섬의 개요와 지반공학적 고려사항)

  • 박성재
    • Proceedings of the Korean Geotechical Society Conference
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    • 1992.10a
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    • pp.107-112
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    • 1992
  • Housing lots and area for industrial construction are very serious problem because of narrow country area and high population density of Korea. Especially the form of Pusan is long from north to south. Since the city is surrounded by the sea, traffic trouble and housing lots problem is very serious condition. To solve these problems, Reclamation & Man-made island is needed. So Pusan city is planning for Man-made Island for 2000 year. I will consider about the content of Man-made Island, which is planned by Pusan, and the character of Geotechnical Engineering.

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