• 제목/요약/키워드: Underwater Construction

검색결과 193건 처리시간 0.025초

돌돔(Oplegnathus fasciatus)에 대한 인위적인 해상풍력발전소 건설소음의 면역학적 영향 (Effect of Artificial Noise from Offshore Wind Power Generation on Immunological Parameters in Rock Bream (Oplegnathus fasciatus))

  • 최광민;주민수;강경식;우원식;김경호;손민영;손하정;박찬일
    • 한국어병학회지
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    • 제34권2호
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    • pp.243-248
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    • 2021
  • Offshore wind power generation is an energy generation field that is rapidly developing owing to the increasing demand for clean energy. However, the physiological response of fish to the underwater noise generated during construction or operation of wind turbines is unclear. We confirmed the effects of sound pressures of 125, 135, 145, and 155 dB/µPa, including 140 dB/µPa (the standard sound pressure for noise damage recognition in South Korea), through serum analysis in rock bream (Oplegnathus fasciatus). High mortality induced by reduced immunity through artificial infection after stimulation was confirmed. These results suggest that rock bream is negatively affected by the noise generated during the construction of offshore wind power plants.

유기질 단열재 종류별 수중정치기간에 따른 pH 변화에 관한 연구 (SOrganic matter insulation by type of Study on pH change according to underwater settling period)

  • 홍상훈;유남규;서은석;김해나;김봉주;정의인
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2019년도 추계 학술논문 발표대회
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    • pp.87-88
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    • 2019
  • Research has been conducted in many fields for the zero energy of domestic buildings. Among them, the development of insulation has become an essential element. Accordingly, researches are being made to improve the performance of organic insulating materials, and PF boards having the lowest thermal conductivity among organic insulating materials have been in the spotlight. However, problems have arisen due to the problems of durability of insulation materials such as PF boards and past acidification, and the durability of insulation materials is deteriorated when moisture or water enters due to crack gaps during the insulation of the basement layer or the external insulation method. In regard to the durability of the insulation, when the organic insulators of different kinds were placed in water, the pH was weakly basic in all organic insulation materials except PF, and the PF was about 4 pH. As a result, the PF should be continuously reviewed, and further analysis should be carried out to determine what causes acidification.

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고로슬래그 미분말과 플라이애시를 사용한 비소성 시멘트 모르타르의 촉진 탄산화에 따른 압축 강도 특성 (Properties of Compressive Strength after Accelerated Carbonation of Non-Sintered Cement Mortar Using Blast Furnace Slag and Fly Ash)

  • 류지수;나형원;형원길
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2023년도 봄 학술논문 발표대회
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    • pp.297-298
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    • 2023
  • In the concrete industry, efforts are being made to reduce CO2 emissions, and technologies that collect, store, and utilize CO2 have recently been studied. This study analyzed the change in compressive strength after the accelerated carbonation test of Non-Sintered Cement(NSC) mortar. Type C Fly Ash and Type F Fly Ash were mixed in a 1:1 ratio and then mixed with Blast Furnace Slag fine powder to produce NSC. The mortar produced was cured underwater until the target age. In addition, an accelerated carbonation test was conducted under the condition of a concentration of 5 (±1.0%) of CO2 gas for 14 days. The mortar compressive strength was measured before and after 14 days of accelerated carbonation test based on the 7th and 28th days of age. As a result of the experiment, the compressive strength was improved in all binder. In general, the compressive strength of NSC mortar subjected to the accelerated carbonation test was similar to that of Ordinary Portland Cement(OPC) mortar not subjected to the accelerated carbonation test.

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해녀복 가상착의를 위한 의복구성적 연구 -제주 해녀복의 특징, 제품 치수, 여유분에 대한 분석- (An Analysis on Clothing Construction for the Virtual Clothing Simulation of Haenyeo Suits -Analyzing the Characteristics, Product Sizes, and Ease of Jeju Haenyeo Suits-)

  • 엄란이
    • 한국의류학회지
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    • 제48권4호
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    • pp.744-755
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    • 2024
  • This study analyzes the characteristics, product dimensions, and ease of haenyeo suits to inform their reproduction. Large, medium, and small haenyeo suits were collected from four manufacturers in Jeju, and their components, cut styles, product dimensions, and ease were analyzed. In the current haenyeo suit design, the upper suit has a collar and a crotch, while the lower suit has a high rise with a gusset. Additionally, there are darts behind the neck in the upper suit and behind the knees in the lower suit. Haenyeo suits have a three-dimensional shape that accommodates the postures needed for haenyeo's underwater activities. The upper suit is finished with a cuffed hem or an uncuffed side seam with a diagonal or stepped cut. The lower suit is cut and sewn with the waist and hem at right angles or with the hem diagonal to the waistline. Haenyeo suit dimensions vary between manufacturers, and the models' body dimensions show that there is little or no ease. In conclusion, haenyeo suit manufacturers currently use the same components; however, they differ in terms of cut styles, sewing methods, dimensions, and designs.

기능을 상실한 보 철거를 통한 하천생태통로 복원 - 곡릉천 곡릉2보 철거를 대상으로 - (Stream Eco-corridor Restoration by Out-aged Small Dam Removal - Focused on Gokreung River Gokreung 2 Small Dam Removal -)

  • 안홍규;우효섭;이동섭;김규호
    • 한국환경복원기술학회지
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    • 제11권2호
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    • pp.40-54
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    • 2008
  • Small and large dams are installed in the course of a stream for maintaining the water level of the stream or obtaining agricultural water. Currently about 18,000 of them are installed in Korea to supply water. However, the environmental problems of small dams are well known : the interruption of stream eco-corridors, deterioration of water quality in the upper reaches of the small dam, changes in the habitats of riparian organisms, damages to the stream scenery. In a very few of these small dams artificial eco-corridors like fishways are installed, but the number is very minimal.Accordingly, to efficiently restore stream eco-corridors by removing these small dams, it will be necessary to closely examine physical impacts, such as changes in the riverbed and changes in the shape of the stream caused by the removal, chemical impacts, such as changes in water quality, and transport and accumulation of contaminated sediments and biological impacts, such as changes in the habitats of organisms, and develop related technologies in advance, and have these technologies verified through demonstration application in the sites. In this study, we analyzed the physical, chemical and ecological impacts of the removal of the above-mentioned small dams, and conducted a research on the demonstration small dam removal project for a spot investigation. As a result, the small dam removal will restore the eco-corridor, there by improving the habitat of fishes and crustaceans. The number of major underwater organisms inhabiting the Gokreungcheon, such as Korean spotted sleepers, Chinese minnows, Microphysogobio yaluensis, Abbottina rivularis, stone morokos, striped shinners, long-nosed barbels, and Chinese mitten crabs, is expected to increase, and the food chain in the ecosystem will improve so that species diversity will improve as well.

운반거리에 따른 국내 산림골재 개발의 지속 개발 방안 (Sustainable Development Plan for Domestic Forest Aggregate Development according to Transport Distance)

  • 이동길;이진영
    • 자원환경지질
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    • 제54권5호
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    • pp.495-503
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    • 2021
  • 골재는 주택 및 도로·항만 등과 같은 SOC건설에 사용되는 주요한 천연자원이며 국가건설의 기본이 되는 기초자재이다. 골재가 공사원가에서 차지하는 비중은 약 4%에 불과하나, 골재는 건설공사 용적의 약 80%를 점유함으로서 건설공사의 양과 질을 좌우하는 필수요소이다. 하천, 수중, 하상, 바다, 육상 골재는 생산시 환경 문제와 제한된 부존량으로 인해 골재수급에 어려움이 발생할 경우 골재의 생산량을 급격하게 증가시키기 어려운 반면에 산림골재는 증산이 비교적 용이하다. 산림골재는 부존량이 풍부해 향후 다른 골재 감축시 대체 골재자원으로 유망하게 평가받고 있으며, 잘 짜여진 계획과 정책에 따라 골재수요에 유연하게 대응할 수 있는 효과적인 골재재원이다. 본 연구에서는 산림골재 개발에 큰 영향을 미치는 운반거리를 중심으로, 운반거리가 긴 경우와 짧은 경우에 대해서 산림골재 활성화 방안과 더불어 현재 산림골재 개발의 난제에 대한 대책을 제시하였다.

떠붙임 모르타르 타일 모듈의 동결융해 저항성 평가 (Enhancing Freeze-Thaw Resilience in Adhered Mortar Tile Modules)

  • 편수정;김규용;김문규;최병철;지성준;남정수
    • 한국건축시공학회지
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    • 제23권3호
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    • pp.241-249
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    • 2023
  • 본 연구에서는 타일 하자 저감을 위해 시공 프로세스를 보완한 타일 모듈을 제작하였다. 타일 모듈은 떠붙임 시멘트 모르타르, 메쉬, 콘크리트로 구성되었다. 하자 발생 저감 가능성을 검토하기 위해 동결융해 시험 전후의 표면상태와 질량 변화율 실험을 실시하였으며 부착강도를 측정하였다. 그 결과, 알루미늄(A) 메쉬는 수중 환경에서, 강철(S) 메쉬는 기중 환경에서 열수축-팽창에 의한 하자가 상대적으로 다수 발생하였고, 메쉬의 크기가 작을수록 부착강도가 상승하는 경향을 보였다.

Fish 군중행동 모델러 (Fish Schooling Behavior Modeler)

  • 김종찬;반경진;김응곤
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2006년도 춘계 종합학술대회 논문집
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    • pp.517-520
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    • 2006
  • 가상 해저 환경 속에서 군중 행동 장면은 영화, 게임 등의 엔터테인멘트 산업 속에서 많은 장면으로 연출된다. 컴퓨터 그래픽스 기술의 발달로 인한 디지털 영화나 애니메이션이 점차 증가함에 따라 이러한 장면이 등장하는 가상캐릭터를 쉽게 접할 수 있다. 컴퓨터 애니메이션에서 등장하는 캐릭터는 가상공간의 생기를 불어넣는 역할을 한다. 이러한 가상캐릭터의 객체수가 증가함에 따라 가상세계에 대한 몰입감을 증대하여 표현해야한다. 국내에서는 가상 환경을 구축하여 실감 체험을 할 수 있는 VR 콘텐츠 기술 개발에 관련하여 군중 장면 처리 및 군중 행동 시스템의 설계 및 구현 등의 연구가 있었으나 군중 행동 모델러 기술 개발을 실용화 할 단계까지는 미치지 못하고 있다. 본 논문에서는 해저환경에서 사실적이고 효율적인 표현을 위해 3D 객체에 행동양식을 부여하고, 상호작용이 가능하도록 fish 군중행동 모델러를 제안한다.

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Nitrox 공기통의 기체 분석에 의한 스쿠버다이버 사망원인 추정에 관한 사례연구 (Case on the Death of Scuba Diver by Analyzing the Air in Nitrox Cylinder)

  • 이준배;유재훈;손성건;성태명;팽기정
    • 한국안전학회지
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    • 제26권2호
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    • pp.42-47
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    • 2011
  • Going underwater is supposed to begin with the history of human beings. At first it was confined to relatively shallow level, less than several meters by holding breath. Recently, deep level diving has been necessary for such purpose as construction, maritime salvage, military operations, research and sports by using SCUBA(self-contained underwater breathing apparatus) equipment. As one goes down into water, the pressure on the diver is increased due to water pressure with depth, usually 1 atm for each 10 m water level. In deep water, mixed gas or nitrox(EAN, enriched air nitrox) could be applied for the divers lest they should get disease due to high pressure. Of these, the former is usually composed of oxygen and inert gas like helium or hydrogen, the latter contains higher oxygen content than that in normal air in which the oxygen concentration is designated by the character "EAN" followed by vol. % of oxygen, for example, "EAN 40" contains 40% of oxygen. In this case, a victim was found at the 39 m below the sea surface breathing air and nitrox in cylinder wrongly marked as EAN 36, which was analyzed to contain 63% of oxygen by GC/TCD. The cause of death could not be exactly related with the oxygen content in the nitrox cylinder, because the accurate depth for the victim to dive was not known, even though the victim was just found at the depth of 39 m. However, the wrongly marked nitrox could be believed to be the main cause of the death at the depth unless there happened any other accident except that during diving.

수상태양광의 시공기술에 관한 실증연구 (The Technique of Installing Floating Photovoltaic Systems)

  • 최영관;이종석
    • 한국산학기술학회논문지
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    • 제14권9호
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    • pp.4447-4454
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    • 2013
  • 2011년 10월 국내 최초로 다목적댐 저수지에 100kW급 수상태양광발전 상용화 실증 플랜트가 합천댐에 설치되었다. 수상태양광발전 설비는 육상에 설치하는 태양광발전 설비와는 달리 수상부유체, 계류장치, 수중케이블 등 설치에 많은 어려움이 있다. 특히 수상이라는 환경적 제약으로 인해 육상 태양광 시공 방법으로 공정 관리를 할 수 없는 많은 변수가 속출한다. 수상태양광발전의 구조체는 수상태양광 모듈 및 기타 전기설비를 수상에 부상시키기 위한 설비로서 바람이나 태풍 등 기상환경에 견뎌야 하고 수질에 악영향을 미치지 말아야하며 시공성, 경제성 등 종합적인 고려가 필요하다. 본 논문에서는 100kW 수상태양광 시공사례를 바탕으로 수상태양광의 구조체, 계류장치, 수중케이블, 전력설비 및 원격감시제어시스템의 시공기술에 대한 기초자료를 제공하였다. 본 연구에서 시공된 100kW 수상태양광은 현재 평균 설비이용률 15%로 운영중에 있다.