• 제목/요약/키워드: Leakage reduction

검색결과 487건 처리시간 0.033초

인적오류 저감을 위한 인간 신뢰도 분석 체계 및 평가에 관한 연구 (Development and Evaluation of Human Reliability Analysis Model for the Reduction of Human Errors)

  • 정경희;변승남;조재립
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2010년도 춘계학술대회 논문집
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    • pp.2048-2051
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    • 2010
  • Almost all companies have paid much attention to the safety management ranging from maintenance to operation even at the stage of designing in order to prevent accidents, but fatal accidents continue to increase throughout the world. In particular, it is essential to systematically prevent such fatal accidents as fire, explosion or leakage of toxic gas at factories in order to not only protect the workers and neighbors but also prevent economic losses and environmental pollution. In addition, HRA may be used to detect the human errors which may cause accidents or trace back to any mistake on the part of workers. Usually, HRA technique is used in association with other risk assessment techniques. Moreover, it can serve to enumerate the human errors which may occur during operation or down-time or correct the existing system to reduce the mistakes. This work focuses on the coincidence of human error and mechanical failure for management of human error, and on some important performance shaping factors to propose a method for improving safety effectively of the process industries.

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용량성 결합을 고려한 CCFL 병렬 구동 (Parallel Operation of CCFLs Considering on Capacitive Coupling)

  • 박정오;김철진;박현철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 제39회 하계학술대회
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    • pp.1007-1009
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    • 2008
  • This paper presents an architecture for driving multiple paralleled cold cathode fluorescent lamps (CCFLs) for back lighting applications. The key to the architecture is a proposed capacitive coupling approach for lamp ignition. This system is consist of a flyback converter, a single inverter to drive multiple lamps and conductive floating reflector. The topology is capable of driving a number of parallel lamps with independent accurate lamp, current regulation and improving cost effectiveness with significant reduction in size and weight, compared to typical high frequency ac ballast. Experimental demonstration results for ten of parallel CCFLs with simultaneous ignition. This like the EEFL it will be able to use the CCFL is the thing. Also, it investigates the effect where the leakage current goes mad to the Lamp.

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다수의 CCFL 구동과 휘도 향상에 관한 연구 (A Study on the Multiple CCFL Operation and Brightness Improvement)

  • 박정오;김철진;박현철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.126-128
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    • 2008
  • This paper presents an architecture for driving multiple paralleled cold cathode fluorescent lamps (CCFLs) for back lighting applications. Multi CCFL operation and increase of brightness, the key to the architecture is a proposed capacitive coupling approach for lamp ignition. This system is consist of a flyback converter, a single inverter to drive multiple lamps and conductive floating reflector. The topology is capable of driving a number of parallel lamps with independent accurate lamp, The capacitive coupling the leakage inductance and stray capacitance creation which it used, current regulation and improving cost effectiveness with significant reduction in size and weight, compared to typical high frequency ac ballast. Experimental demonstration results for ten of parallel CCFLs with simultaneous ignition.

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Aloe vera peel 추출물의 Streptococcus mutans JC-2에 대한 항균활성 (I) (Antimicrobial Activity of Extracts from Aloe vera peel against Streptococcus mutans JC-2(I))

  • 박정순;신용서;류일환;이갑상
    • 한국식품영양학회지
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    • 제13권2호
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    • pp.139-145
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    • 2000
  • To separate anticaries and antiinflammation from Aloe vera peel, we investigated a inhibited effect of Streptococcus mutans JC-2 that was antibiosis, glucosyltransferase activity about aloe-emodin and barbaloin. Aloe-emodin and barbaloin had strong antibiosis activity against Streptococcus mutans JC-2, they were especially antibiosis effect to low growth and prolong lag phase at attachment concentration 100$\mu\textrm{g}$/mL. The reduction rate of a culture fluid became to lessen than the comparison group for aloe-emodin and barbaloin. The intracellular materials of Streptococcus mutans JC-2 were to leakage as much as attachment concentration addition of aloe-emodin and barbaloin but there was no significant difference membrane demage between two active substances. The activity of GTase was inhibited by aloe-emodin and barbaloin and their inhibition rate was respectively 99.8%, 98.4% at the attachment concentration 100$\mu\textrm{g}$/mL.

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온실가스($CO_2$) 지중저장과 암반공학적 기술요소 (Greenhouse Gas ($CO_2$) Geological Sequestration and Geomechanical Technology Component)

  • 김형목;박의섭;신중호;박용찬
    • 터널과지하공간
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    • 제18권3호
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    • pp.175-184
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    • 2008
  • 본 고에서는 온실가스 감축방안으로 배출 $CO_2$를 지하심부에 격리 저장시키는 지중 저장기술의 국내외 기술동향을 살펴보고 지반 및 암반공학적 관련기술로서 $CO_2$ 주입에 따른 대상지층의 역학적 안정성 및 누출경로 평가를 위한 열-수리-역학적 연계해석기술 및 적용사례, 기술개발요소를 소개하였다.

음향 인클로저의 환기창을 통한 투과소음 능동제어 (Active Control of Noise Transmitted through a Window of Enclosures)

  • 지수민;홍진숙;정의봉
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.670-672
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    • 2014
  • In this study, we investigate active control of noise transmitted through a window of enclosures minimizing the acoustic power. To reduce noise of the enclosures, passive methods with absorbing material are generally used. The passive methods, however, are limited use due to the vantilation windows. In this case, these windows are path of noise leakage. Feedforward active noise control technology is applied to minimize the sound power from the enclosure. The feedforward controller is implemented with FIR filter based on the transfer functions calculated numerically. The controller reflects the delay due to FIR filter. The noise transmitted through the window is actively controlled, and the reduction of the power is obtained by 15dB.

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인클러져 개구부 투과소음 능동제어 (Active Control of Transmitted Noise through Opening of Enclosures)

  • 이한울;홍진숙;정의봉
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2012년도 추계학술대회 논문집
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    • pp.733-738
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    • 2012
  • This paper presents active noise control for the reduction of transmission noise passing through opening of enclosures. Enclosures are essential measure to protect noise propagation from operating machinery. Access openings of the enclosures are important path of noise leakage. First, we modeled and analyzed the noise characteristics passing through the openings of the enclosure generated by the operation of the machinery based on the finite element method. We then implemented a feedforward controller to actively control the acoustic power through the opening. Finally, we conducted optimization of placement of the reference sensors for several cases of the number of sensors. A good control performances were achieved using a minimum number of microphones arranged a optimal placement.

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Flexible Plasma Sheets

  • Cho, Guangsup;Kim, Yunjung
    • Applied Science and Convergence Technology
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    • 제27권2호
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    • pp.23-25
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    • 2018
  • With respect to the electrode structure and the discharge characteristics, the atmospheric pressure plasma sheet of a thin polyimide film is introduced in this study; here, the flexible plasma device of a dielectric-barrier discharge with the ground electrode and the high-voltage electrode formulated on each surface of a polyimide film whose thickness is approximately $100{\mu}m$, that is operated with a sinusoidal voltage at a frequency of 25 kHz and a low voltage from 1 kV to 2 kV is used. The streamer discharge is appeared along the cross-sectional boundary line between two electrodes at the ignition stage, and the plasma is diffused on the dielectric-layer surface over the high-voltage electrode. In the development of a plasma sheet with thin dielectric films, the avoidance of the insulation breakdown and the reduction of the leakage current have a direct influence on the low-voltage operation.

아이핀(i-PIN)의 가치창출효과 추정 (Estimating Value Creation Effects of i-PIN)

  • 장원창;신일순
    • 한국IT서비스학회지
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    • 제12권2호
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    • pp.185-193
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    • 2013
  • This paper analyzes the effects of i-PIN focusing on the positive value creation rather than the negative loss reduction from the viewpoint of internet company. Empirical tests are run to examine what determines the use of i-PIN and whether i-PIN users participate in e-commerce, communication, and SNS activity. Our findings are as follows. First, the reason for using i-PIN lies in the experience of privacy infringement rather than a high value on privacy protection. Second, i-PIN users tend to participate in the online activity such as e-commerce, communication, SNS. Third, the marginal effect of i-PIN adoption amounts to 2~9% of increase in the online activity. With the results, we expect that i-PIN adoption leads to sales increase and new customer acquisition as well as privacy leakage decrease and it provides logic to solve social underinvestment problem in privacy protection.

수돗물 공급 안정화를 위한 광역상수도 관로 안정화 타당성 연구 (Feasibility Study of Multi-regional Transmission Main Stabilization for Sustainable Water Supply)

  • 이재범;이충성;정관수
    • 상하수도학회지
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    • 제27권3호
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    • pp.395-404
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    • 2013
  • The risk of pipe-bursting in multi-regional transmission mains consisting of 89 % of singled pipeline is so high that pipeline stabilization project is required such as renewal and replacement, pipe paralleling, emergency ties. Pipeline stabilization projects could be postponed at the step of initial decision-making because effect of this project is intangible benefit like activation of economic, improvement of welfare related to water. This study is to suggest quantified economical feasibility model for intangible benefit presumption to solve above problem. Cost reduction of emergency water supply, leakage, burst restore and energy efficiency improvement was altered and applied. As a result of economic analysis taking into account estimated benefit and cost under discount rate 5.5 %, service life 40 years, sufficient economic feasibility analyzed with B/C 2.45, NPV 317,700 million won, IRR 9.09 %.