• Title/Summary/Keyword: 복합노출

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An Experimental Study on the Mechanical Properties of High Modulus Carbon-Epoxy Composite in Salt Water Environment (염수 환경에 노출된 고강성 탄소/에폭시 복합재의 물성치 변화 연구)

  • Moon, Chul-Jin;Lee, Cheong-Lak;Kweon, Jin-Hwe;Choi, Jin-Ho;Jo, Maeng-Hyo;Kim, Tae-Gyeong
    • Composites Research
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    • v.21 no.6
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    • pp.1-7
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    • 2008
  • The main objective of this study is to investigate the effect of salt water on the mechanical properties of a high modulus carbon-epoxy composite. Specimens were made of a carbon-epoxy composite UPN139B of SK Chemical and tested under inplane tension and shear after 0, 1, 3, 6, 9, and 12 months immersion in 3.5% salt water. Acceleration technique such as temperature elevation was not used. The tensile strengths and modulli in fiber and matrix direction did not show any remarkable degradation until 12 months immersion. In contrast to the tensile properties, shear strength and modulus started to gradually decrease up to about 10% of values of dry specimens after 12 months immersion. It was confirmed through the test that the material UPN139B can be an effective material for the shell structures in salt water to resist against the external pressure buckling because of the high fiber directional modulus and corrosion resistance.

DNA damages with Fpg/Endo Ⅲ FLARE Assay in cynomolgus monkeys exposed to stainless steel welding fume (용접흄 흡입노출 영장류에서 Fpg/Endo Ⅲ FLARE Assay를 이용한 DNA 손상 및 회복)

  • Rim, Kyung Taek;Kim, Soo Jin;Chung, Yong Hyun;Kim, Hyeon Yeong;Maeng, Seung Hee;Yu, Il Je
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.17 no.4
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    • pp.272-281
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    • 2007
  • 선박제조업을 비롯한 운송업 및 건축업 등의 다양한 분야에서 용접기술이 이용되어 옴에 따라 용접근로자들에 대한 산업보건학적 관심이 높아지고 있다. 노출정도가 다양하기는 하지만 용접흄은 6가 크롬을 비롯한 금속화합물과 유해가스, 화학물질 등을 복합적으로 포함하고 있는 스테인레스 스틸 용접흄에 대한 유전독성영향을 평가하기 위하여 흡입챔버를 이용, 실험동물인 영장류에 스테인레스 스틸 용접흄을 노출시키고 혈액 내 lymphocytes에 생성된 용접흄 노출농도 및 시간별 DNA 손상정도 및 그 회복효소를 측정함으로써, 유해성이 완전하게 확인되지 않은 용접흄에 노출되어 나타날 수 있는 암을 비롯한 심각한 건강영향을 예방하기 위한 각 지표들을 찾아 그 유용성을 비교하고자 하였다. 영장류를 노출시키기 위해 robotic arm을 장치한 영장류 흡입노출 시스템을 개발하였으며, 이 노출 시스템을 이용하여 수컷 영장류 6마리에 대해 용접흄 노출시험을 실시하였는데 실험군은 대조군 2, 저농도 ($31mg/m^3$) 노출군 2, 고농도 ($63mg/m^3$) 노출군 2마리로 구성하였고, 1일 2시간씩 일주일에 5일 동안 용접흄에 노출시켰다. 노출 농도는 지속적으로 모니터링 하였고, 노출과정 중에 영장류의 혈액을 채취하여 lymphocytes를 분리, 단세포 DNA 손상을 선별하기 위해 DNA 손상회복 효소인 E. coli formamidopyrimidine-DNA glycosylase (Fpg)와 endonuclease Ⅲ (Thymine Glycol-DNA glycosylase) 투여와 Comet asaay (single cell gel electrophoresis, 단세포겔전기영동기법)를 결합시켜 이용하는 Fpg/Endo III FLARE 분석법을 사용하였다. Fpg enzyme에 의한 olive tail moment값의 변화는 16주 노출군부터 노출부검(34주)군 까지 노출농도가 높아짐에 따른 olive tail moment 기하평균 값의 양 반응관계를 보기는 어렵지만, 고농도군의 경우 27주 노출군에서 가장 높은 olive tail moment 값을 보이고 이후 차츰 감소하였다. 한편 16주에서 22주까지의 노출기간에서는 대조군에 비해 노출군에서 DNA손상정도(olive tail moment값)는 모두 유의하게 높았으나, 6, 12, 18, 25, 31, 33, 35주간 노출하였을 때는 다른 결과를 보였다. 각 실험군의 Fpg enzyme에 의한 tail length값의 분포를 살펴볼 때, 저농도군 및 고농도군에서 27주간 노출하였을 때 가장 높은 tail length 값을 보이고 이후 차츰 감소하는 경향을 보였다. 또한 16, 22주간 노출하였을 때 대조군에 비해 노출군에서 tail length 값이 유의하게 높았으나, 20주간에서만 양 반응관계가 관찰되었고, 다른 주간에서는 양 반응 및 기간 반응관계를 나타내지는 않았다. Endo III enzyme에 의한 olive tail moment값의 변화는 기간별 노출군에서 대조군에 비해 높은 DNA손상정도(olive tail moment값)를 나타내는 결과들이 있었지만, 10, 12, 16, 22, 25, 31주간 노출하였을 때 등 상당수 노출기간에서 반응관계를 나타내지는 않았다. 각 실험군의 Endo III enzyme에 의한 tail length값의 분포를 살펴볼 때, 18, 20, 27, 33주간 노출하였을 때 대조군에 비해 노출군에서 tail length 값이 조금 높았지만, 양 반응 및 기간 반응관계를 보이지 않았고 수치의 크기가 불규칙하게 변화하였다. 즉, DNA에 있어 산화된 pyrimidine을 형성하여 손상된 부위의 염기를 제거함으로써 AP site (abasic site)를 만들고 이들이 Comet assay를 통해 break로 전환된 것을 포함한 DNA손상을 측정하기 위하여 endonuclease III (Endo III)를 첨가시킨 Endo III FLARE 분석법을 실시한 결과, 본 연구에서 나타난 결과는 용접흄 노출 영장류에서 Olive tail moment 및 tail length 공히 노출량 및 노출기간 반응관계를 볼 수 없었다. Endo III FLARE 분석법을 통한 산화적 DNA 손상지표는 영장류에 적용하기에는 적응반응현상으로 대조군과 유의한 차이도 관찰할 수 없었고 더욱이 역으로 대조군에서의 자연발생적 수치가 더 높아질 수 있어 용접흄 노출 영장류의 모니터링 지표로 사용하기에는 제한점이 있었다.

A Study on the character of Urban Entertainment Center in multi-anchor and exposure time - Focusing on Cheongryanri station and Yongsan station - (집객시설과 노출시간에 따른 도심 엔터테인먼트형 복합상업시 설(UEC)의 특징에 관한 연구 - 청량리역과 용산역을 중심으로 -)

  • Kim, Hyeongjung
    • Korean Institute of Interior Design Journal
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    • v.22 no.1
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    • pp.283-290
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    • 2013
  • The change of shopping environment created new emerging type of shopping center after 1990's, Urban Entertainment Center(UEC) in northen America. One hand traditional shopping center was retail-centered, the other hand UEC is entertainment-centered and offers the trinity of synergy. Each components, that are retail, dining and entertainment, play a role of drawing people, extending duration of visiting and making people revisit then the synergy makes commercial profit in shopping center. As northen America many of shopping centers with complex have been built in Korea since 2000 and some projects is planning by the change of shopping environment and regenerating urban. Although the term of "UEC" is used in Korea, it seems to be added entertainment facilities to shopping center without considering on commercial strategy. This study will take a look at mix and duration of visit which ULI stresses in UEC development and comparing with those of Yongsan Station and Chyeongrangri Station which are built recently in seoul, it will get characters and situation of these UECs. Finally, the analysis is to be used as a planning data in UEC development.

Study on the Application of Site for Exposure Type of Complex Waterproofing Method with Liquefied Waterproof using of Vertical Type Reinforcing Sheet Material Reinforced Sheet Rising System in the Roof Tops (돌기 시스템을 이용한 입체보강형시트의 옥상노출복합방수공법 적용에 관한 재료 및 공법적 연구)

  • Oh, Sang-Keun;Son, Mun-Se;Kim, Jin-Seong;Yeo, In-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2006.11a
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    • pp.17-20
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    • 2006
  • It often happen water leakage that roof membrane have a poor condition such as direct exposed to rain, ultraviolet lays, temperature change compare with other part of waterproofing. There are difficult to maintain the quality of waterproofing and durability due to use only few waterproofing materials in practical in spite of development and use the various waterproofing material as solution of these poor condition. Therefore, in this thesis, I would like to know the property to apply field and suggest other method to develop for this waterproofing method to adopt various field condition for roof tops, as searching exposed and complex waterproofing technology for roof tops which is reinforced sheet using rising system have a regular pitch, depth, space.

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Study on the Application of Site for Exposure Type of Complex Waterproofing Method with Liquefied Waterproof using of Vertical Type Reinforcing Sheet Material Reinforced Sheet Rising System in the Roof Tops (돌기 시스템을 이용한 입체보강형시트의 옥상노출복합방수공법 적용에 관한 재료 및 공법적 연구)

  • Oh, Sang-Keun;Son, Mum-Se;Kim, Jin-Seong;Yeo, In-Soo
    • Journal of the Korea Institute of Building Construction
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    • v.6 no.4 s.22
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    • pp.69-75
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    • 2006
  • It often happen water leakage that roof membrane have a poor condition such as direct exposed to rain, ultraviolet lays, temperature change compare with other part of waterproofing. There are difficult to maintain the quality of waterproofing and durability due to use only few waterproofing materials in practical in spite of development and use the various waterproofing material as solution of these poor condition. Therefore, in this thesis, I would like to know the property to apply field and suggest other method to develop for this waterproofing method to adopt various field condition for roof tops, as searching exposed and complex waterproofing technology for roof tops which is reinforced sheet using rising system have a regular pitch, depth, space.

Stress Perception and Psychopathology in Workers Exposed to Mixtures of Organic Solvents (복합유기용제에 노출된 근로자들의 스트레스지각 및 정신병리)

  • Kim, Chan-Hyung;Koh, Kyung-Bong
    • Korean Journal of Psychosomatic Medicine
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    • v.1 no.1
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    • pp.59-66
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    • 1993
  • A comparison was made between workers exposed to organic solvents and those not exposed to them regarding stress perception and psychopathology, using GARS scale and SCL-90-R. The exposed group scored significantly higher than the non-exposed group in stress perception relevant to job-wort changes in relationship, sickness or injury, financial, and overall global area. The exposed group was significantly higher in somatization scale than the non-exposed group. However, there was no significant correlation between duration of exposure and psychopathology. In each of the groups. female workers showed more psychopathology than male ones. Age showed significantly nagative correlation with psychopathology. These results suggest that the exposed group shows higher stress perception and more psychopathology than the non-exposed group. Thus. it is emphasized that health policy makers as well as employers should pay more attention to health. espcially mental health for the workers exposed to organic solvents.

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An Experimental Study about appling non-Exposure waterproofing method which combines the Cement Polymer Modified Waterproof Membrane coating and Self adhesive Rubberized Asphalt sheet to the Roof Structure. (무기질계 탄성 도막재와 자착식 고무 아스팔트 시트를 결합한 지붕구조물 비노출 방수공법에 관한 실험적 연구)

  • Moon, You-Seok;Lee, Sun-Gyu;Song, Je-Yeong;Gwak, Gyu-Seong;Oh, Sang-Keun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.613-616
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    • 2008
  • This study is about appling non-exposure waterproofing method which combines the Cement Polymer Modified Waterproof Membrane coating and Selfadhesive Rubberized Asphalt sheet to the Roof Structure, Because there are a lot of problems in previous methods. So We had the performance tests using waterproofing method which combines two materials, and we analyzed the results. This study showed us very important results. We had bond strength test and tensile test under high, normal and low temperature, and the results were successful. And we also tested for coping with crack and movement. We found that tested materials were safe in those conditions. I think that Non-Exposure waterproofing method which combines the Cement Polymer Modified Waterproof Membrane coating and Selfadhesive Rubberized Asphalt sheet is available to concrete structure.

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Feasibility Study on Packaged FBG Sensors for Debonding Monitoring of Composite Wind Turbine Blade (풍력발전기 복합재 블레이드의 접착 분리 모니터링을 위한 패키징 광섬유 브래그 격자 센서 탐촉자의 사용성 검토)

  • Kwon, Il-Bum;Choi, Ki-Sun;Kim, Geun-Jin;Kim, Dong-Jin;Huh, Yong-Hak;Yoon, Dong-Jin
    • Journal of the Korean Society for Nondestructive Testing
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    • v.31 no.4
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    • pp.382-390
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    • 2011
  • Smart sensors embedable in composite wind turbine blades have been required to be researched for monitoring the health status of large wind turbine blades during real-time operation. In this research, the feasibility of packaged FBG sensor probes was studied through the experiments of composite blade trailing edge specimens in order to detect cracking and debonding damages. The instants of cracking and debonding generated in the shear web were confirmed by rapid changes of the wavelength shifts from the bare FBG sensor probes. Packaged FBG sensor probes were proposed to remove the fragile property of bare FBG sensor probes attached on composite wind blade specimens. Strain and temperature sensitivity of fabricated probes installed on the skin of blade specimen were almost equal to those of a bare FBG sensor. Strain sensitivity was measured to be ${\mu}{\varepsilon}$/pm in a strain range from to 0 to 600 ${\mu}{\varepsilon}$, and the calculated temperature sensitivity was to be 48 pm/$^{\circ}C$ in the heating test up to 80 degree.

Aging Properties from Forest-fire Simulated Acceleration of Porcelain Insulators for Transmission Line (송전용 애자의 산불 복합가속열화 특성)

  • Han, Se-Won;Choi, In-Hyuk;Lee, Dong-Il;Lee, Won-Kyo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.114-114
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    • 2010
  • 산불에 노출되는 경우 열충격으로 작용하는 패턴과 특성을 검토하여 가속열화시험에 반영하는 것이 필요하다. 본 연구에서는 산불환경을 모의하여 복합열화시험을 실시하기위해 복합가속열화 챔버를 구축하였다. 온도는 주로 $200^{\circ}C$에서 최대 $1000^{\circ}C$까지 변화를 주면서 예비시험과 본시험 실하였다.

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