• Title/Summary/Keyword: VCE

검색결과 69건 처리시간 0.019초

VCE에 의한 건물피해예측에 관한 연구 (A Study on Estimation of Structure Damage caused by VCE)

  • 임사환;이종락;허용정
    • 한국안전학회지
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    • 제22권5호
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    • pp.65-70
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    • 2007
  • This paper is estimation of structure damage caused by VCE(Vapor Cloud Explosion) in enclosure. As we estimate the influence of damage which occur at gas facility in factory. We can utilize the elementary data of safety distance. In this study, the influence of over-pressure caused by VCE in enclosure was calculated by using the Hopkinson's scaling law and the accident damage was estimated by applying the influence on the adjacent structure into the probit model. As a result of the damage estimation conducted by using the probit model, both the damage possibility of explosion overpressure to structures of 20 meters away and to glass bursting of 80 meters away was nearly zero in open space explosion.

밀폐공간에서의 VCE에 의한 충격파 고찰 (A Study on the Shock Wave Caused by VCE in Enclosure)

  • 임사환;이종락;허용정
    • 대한기계학회논문집B
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    • 제32권1호
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    • pp.1-6
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    • 2008
  • In order to establish detailed plans for fire protection and reduce the possible fire accidents in the future, a study on the shock wave caused by VCE(Vapor Cloud Explosion) is very important. Destruction phenomena of structure by gas explosion is due to the explosion pressure and heat. Explosion pressure is a kind of energy converted from the gas mixture explosion. Therefore, the propagation progress of shock wave and flame is very important. This study investigated the shock wave caused by VCE in enclosure with opened vent port. From a result, the vent port of top at the straight line of ignition and leak location was opened most rapidly, and the vertical vent port not opened.

Copolymerization of 4′-vinylbenzo-15-crown-5 with Di(ethylene glycol) Ethyl Ether Acrylate

  • Jin, Long Yi;Mah, Soukil
    • Fibers and Polymers
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    • 제3권2호
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    • pp.49-54
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    • 2002
  • Radical copolymerization behavior of 4'-vinylbenzo-15-crown-5, a vinyl monomer having a pendant 15-membared crown ether unit (VCE) with di(ethylene glycol) ethyl ether acrylate (DEGEEA) was carried out in toluene solution using 2,2-azobisisobutyronitrile (AIBN) as an initiator. The copolymers were characterized by means of FT-IR, $^1{H-NMR}$, and $^{13}{C-NMR}$ . The reactivity ratio of VCE and DEGEEA, determined by Fineman-Ross and Kelen-Tudos method, gave values 0.55 for VCE, and 0.11 for DEGEEA respectively.

Can we substitute the intuition of an experienced bridge inspector by monitoring?

  • Wenzel, Helmut;Tanaka, Hiroshi;Hollrigl-Binder, Michaela;Allmer, Helga
    • Smart Structures and Systems
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    • 제15권3호
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    • pp.577-592
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    • 2015
  • Damage quantification is a major goal of the SHM community. Methodologies to introduce a quantity for actual condition of a structure into the assessment process are desired. The idea that the condition of a structure is represented in the character of its dynamic response is fully accepted by the SHM community. The VCLIFE methodology quantifies condition analyzing input from monitoring.

밀폐공간에서의 VCE에 의한 충격파 고찰 (A Study on the Shock Wave caused by VCE in Enclosure)

  • 임사환;허용정;이종락
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회A
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    • pp.54-59
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    • 2007
  • In order to establish detailed plans for fire protection and reduce the possible fire accidents in the future, a study on the shock wave caused by VCE(Vapor Cloud Explosion) is very important. Destruction phenomena of structure by gas explosion is due to the explosion pressure and heat. Explosion pressure is a kind of energy converted from the gas mixture explosion. Therefore, the propagation progress of shock wave and flame is very important. This study investigated the shock wave caused by VCE in enclosure with opened vent port. From a result, the vent port of top at the straight line of ignition and leak location was opened most rapidly, and the vertical vent port not opened.

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밀폐공간에서의 VCE에 의한 건물피해예측에 관한 연구 (A Study on Estimation of Structure Damage caused by VCE in Enclosure)

  • 임사환;허용정;이종락
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2007년도 춘계학술발표논문집
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    • pp.42-45
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    • 2007
  • This paper is estimation of structure damage caused by VCE(Vapor Cloud Explosion) in enclosure. As we estimate the influence of damage which occur at gas facility in factory. We can utilize it the elementary data of safety distance. In this study, the influence of explosion over-pressure caused by VCE in enclosure was calculated by using the Hopkinson's scaling law and the accident damage was estimated by applying the influence on the adjacent structure into the probit model. As a result of the damage estimation conducted by using the probit model, both the damage possibility of explosion overpressure to structures 20 meters away and that of overpressure to glass bursting 80m meters away showed nothing.

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교류 전동기 구동을 위한 IPM(Intelligent Power Module) IGBT 스위치 성능 분석 방법 개발 (Development of IPM(Intelligent Power Module) IGBT switch performance evaluation system for the driving of the A.C. motor)

  • 최중경
    • 한국정보전자통신기술학회논문지
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    • 제15권4호
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    • pp.291-297
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    • 2022
  • 본 논문은 가전용 교류 전동기 구동을 위한 인버터 회로에 포함된 지능형 스위칭 모듈인 IPM 모듈에 대한 특성 및 신뢰성 계측 회로 설계 방법에 대한 연구이다. IPM은 전동기 구동기의 핵심 부품으로 그 스위칭 특성이 서보 구동 중에 일관되게 유지돼야 한다. 그 특성 중 스위치 온 특성을 결정하는 콜렉터-에미터간 도통 전압 Vce(on) 특성이 중요하다. 인버터 구성의 핵심 부품인 IPM은 여러 브랜드의 제품이 생산되고 있기 때문에 응용시스템의 최적 성능을 위해서는 IPM의 제품군에 따른 IGBT 스위치의 콜렉터-에미터간 도통 전압 Vce(on) 값을 측정하기 위한 방법 및 계측 평가 시스템이 필요하다. 제안된 방법은 제조사별 IPM이 전동기 구동회로에 장착된 상태에서 부하에 따른 Vce(on) 값을 계측 평가할 수 있는 새로운 방법으로 사용자 회사 입장에서는 중요한 설비가 될 수 있다.

Current status of image-enhanced endoscopy in inflammatory bowel disease

  • Young Joo Yang
    • Clinical Endoscopy
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    • 제56권5호
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    • pp.563-577
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    • 2023
  • In inflammatory bowel disease (IBD), chronic inflammation leads to unfavorable clinical outcomes and increases the risk of developing colorectal neoplasm (CRN); thereby highlighting the importance of endoscopically evaluating disease activity as well as detecting and characterizing CRN in patients with IBD. With recent advances in image-enhanced endoscopic (IEE) technologies, especially virtual chromoendoscopy (VCE) platforms, this review discusses state-of-the-art IEE techniques and their applicability in assessing disease activity and surveillance colonoscopy in patients with IBD. Among various IEE, VCE demonstrated the capacity to identify quiescent disease activity. And endoscopic remission defined by the new scoring system using VCE platform better predicted clinical outcomes, which may benefit the tailoring of therapeutic strategies in patients with IBD. High-definition dye-chromoendoscopy (HD-DCE) is numerically superior to high-definition white light endoscopy (HD-WLE) in detecting CRN in IBD; however, discrepancy is observed in the statistical significance. VCE showed comparable performance in detecting dysplasia to HD-WLE or DCE and potential for optical diagnosis to differentiate neoplastic from nonneoplastic lesions during surveillance colonoscopy. Applying these novel advanced IEE technologies would provide opportunities for personalized medicine in IBD and optimal treatment of CRN in patients with IBD.

액화수소 충전스테이션에서 VCE로 인한 피해영향평가에 관한 연구 (A Study on the Evaluations of Damage Impact due to VCE in Liquid Hydrogen Charging Station)

  • 이수지;천영우;이익모;황용우
    • 한국가스학회지
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    • 제21권5호
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    • pp.56-63
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    • 2017
  • 전세계적으로 수소 충전 스테이션 구축에 많은 투자와 지원을 하고 있는 실정이다. 그러나 수소는 폭발범위가 넓고 확산이 빠른 기체이다. 본 연구에서는 액화수소를 취급하는 소규모~대규모 충전스테이션을 대상으로, 사고시 발생하는 VCE로 인한 피해영향범위를 산출하고, 프로빗 모델을 통해 주변의 인적, 물적 피해를 예측하였다. 더불어, 벤트스택 끝단에서 발생 가능한 Jet fire를 시나리오로 선정하여 최적 높이를 설정하였다. 피해영향범위는 관심과압 6.9kPa을 기준으로 하여, 소규모 저장시설의 경우 8.24m, 중규모 14.10m, 대규모 22.38m이다. 폐출혈로 인한 인체 피해는 소규모와 중규모가 각각 50m, 대규모 100m였으며, 구조물 손상에 따른 피해는 소규모 200m, 중규모 300m 및 대규모 500m이다. 벤트스택의 최적높이는 소규모 4.7m, 중규모 8.8m 및 대규모 16.9m이다.

LPG충전소에서 증기운폭발이 주변건물에 미치는 영향의 정량적 해석 및 평가에 관한 연구 (A Study on the Quantitative Analysis and Estimation for Surround Building caused by Vapor Cloud Explosion(VCE) in LPG Filling Station)

  • 임사환;허용정
    • 한국안전학회지
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    • 제25권1호
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    • pp.44-49
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    • 2010
  • This paper is estimation of structure damage caused by Explosion in LPG(Liquefied Petroleum Gas) filling station. As we estimate the influence of damage which occur at gas storage tank in filling station. We can utilize the elementary data of safety distance. In this study, the influence of over-pressure caused by VCE(Vapor Cloud Explosion) in filling station was calculated by using the Hopkinson's scaling law and the accident damage was estimated by applying the influence on the adjacent structure into the probit model. As a result of the damage estimation conducted by using the probit model, both the damage possibility of explosion overpressure to structures of max 265 meters away and to glass bursting of 1150 meters away was nearly zero in open space explosion.