• 제목/요약/키워드: Won Bang

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터널 지보특성 개선을 위한 보강함성섬유 숏크리트공법 연구 (A Study on the construction method of reinforced shotcrete using structural synthetic fiber)

  • 한일영;김방래;원종필
    • 한국터널공학회:학술대회논문집
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    • 한국터널공학회 2005년도 학술발표회 논문집
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    • pp.259-261
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    • 2005
  • The needs of improving the performance of wet shotcrete has become one of the most important issues in the tunnel field. The aim of this paper is to research the construction method of reinforced shotcrete using structural polymer fiber which exhibits a high quality in toughness and durability for the support of tunnel.

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모델링 오차를 고려한 신경망 기법 기반 손상추정방법 (Neural Networks-Based Damage Detection for Bridges Considering Errors in Baseline Finite Element Models)

  • Lee, Jong-Jae;Yun, Chung-Bang;Lee, Jong-Won;Jung, Hie-Young
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2003년도 봄 학술발표회 논문집
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    • pp.382-387
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    • 2003
  • In this paper, a neural networks-based damage detection method using the modal properties is presented, which can effectively reduce the effect of the modeling errors in the baseline finite element model from which the training patterns for the networks are to be generated. The differences or the ratios of the mode shape components between before and after damage are used as the input to the neural networks in this method, since they are found to be less sensitive to the modeling errors than the mode shapes themselves. Results of laboratory test on a simply supported bridge model and field test on a bridge with multiple girders confirm the applicability of the present method.

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초기 재령 콘크리트의 모니터링을 위한 개선된 레일리파 속도 측정 기법 (Improved Rayleigh Wave Velocity Measurement Technique for Early-age Concrete Monitoring)

  • 신성우;윤정방;;송원준
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2006년도 정기 학술대회 논문집
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    • pp.97-103
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    • 2006
  • A modified one-sided measurement technique is proposed for Rayleigh wave (R-wave) velocity measurement in concrete. The scattering from heterogeneity may affect the waveforms of R-waves in concrete, which may make the R-waves dispersive. Conventional one-sided techniques do not consider the scattering dispersion of R-waves in concrete. In this study, the maximum energy arrival concept is adopted to determine the wave velocity by employing its continuous wavelet transform. Experimental study was performed to show the effectiveness of the proposed method. The present method is applied to monitor the strength development of early-age concrete. A series of experiments were performed on early-age concrete specimens with various curing conditions. Results reveal that the proposed method can be effectively used to measure the R-wave velocity in concrete structures and to monitor the strength development of early-age concrete.

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Arena와 Six Sigma를 이용한 공정개선을 위한 연구 (A Study on Improvement of Production Process Using Arena and Six Sigma)

  • 임석진;박송이;변종원;조재경;방형수;권선미;이우능
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2007년도 추계학술대회
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    • pp.9-19
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    • 2007
  • This study deals with the improvement of production process on a flow production system with the consideration of six sigma. We analyze the production process and survey the important factors of improvement of productivity. Using a six sigma, we find strategic point and suggest a reformation of production process. We applied a simulation technique to simulate the production line proposed by the result of the Six sigma. With the result of the simulation, this study analyzes the propriety of production line and proposes the alternatives of new production process.

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부하-강도 분석을 이용한 격막형 펄스분리장치의 내열강도에 대한 신뢰성 예측 사례연구 (Case Study on Reliability Prediction of Barrier Type Pulse Separation Device using Stress-Strength Analysis)

  • 이동원;정세용;이방업;정규동;박부희;안동근;장중순
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제15권2호
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    • pp.124-130
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    • 2015
  • A stress-strength analysis is used to assess the reliability of a multi-pulse rocket motor system. Main stress is found to be thermal during explosion and the distribution is obtained by simulation. The strength distribution is derived from the results of actual specimen tests. The failure rate of barrier type pulse separation device is estimated.

Melandrin유도체의 진통 소염 및 항바이러스 효과 (Analgesic, Anti-inflammatory and Antiviral Effects of Melandrin Derivatives)

  • 임증기;이은방;우원식;이강노;이영순;마은숙
    • 약학회지
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    • 제38권3호
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    • pp.345-350
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    • 1994
  • Fourteen melandrin derivatives(I-XIV) were investigated on analgesic, anti-inflammatory and antiviral activities . Compound I [N-(p-hydroxybenzoyl)-5-hydroxyanthranilic acid methvl ester], Xll [N-(2-phenoxypropionyl)-5-hydroxy anthranilic acid propyl ester and XIV [N-(2-phenoxypropionyl)-5-hydroxyanthranilic acid exhibited analgesic activity in tail pressure and Randall-Selitto method. But no anti-inflammatory activity was shown. Compound I exhibited weak antiviral activity on Herpes simplex virus type I F strain by virus-induced cytopathic effect(CPE) assay and it's selectivity index(Sl) was 8.17.

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철도차량 객실화재 안전감시 시스템 (Rolling Stock Passenger Compartment Fire Safety Surveillance System)

  • 손영진;이강원;방연근
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2005년도 춘계학술대회 논문집
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    • pp.58-63
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    • 2005
  • It is an emergency which is in the process of existing using of passenger compartment equipment of the rolling stock to sprout and interphone wiring and by the fire sensor which perceives the smoke in the use passenger car ceiling the receiver which is to driver's cabin it leads and the fire occurrence alarm voice sprouts carried on shoulder but, by no. of the car indication ramp it divides the corresponding vehicle and from inside the passenger compartment of the rolling stock from fire occurrence hour driver's cabin corresponding passenger no. of the car. It is accurate and in order it will be able to perceive. It will be able to confront initially quickly with the technique which it composes. It is regarding the fire safety surveillance system it will be able to embody at the expense which is cheap in order to use existing wiring.

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Gastroprotective Activity of the Unripe Fruit Extract of Juglans mandshurica in Rats

  • Lee, Eun-Bang;Hyun, Jin-Ee;Li, Da-Wei;Jeong, Choon-Sik;Shin, Seung-Won;Cho, Sung-Ig;Jhon, Gil-Ja;Lee, Eun-Hee
    • Natural Product Sciences
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    • 제7권3호
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    • pp.87-89
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    • 2001
  • The unripe fruit extract of Juglans mandshurica showed significant inhibition on aspirin and indomethacin induced gastric lesion at an oral dose of 1000 mg/kg. The extract did not show inhibition of aspirin induced ulcer and Shay ulcer at the doses of 500 and 1000 mg/kg. The results indicate that the extract had a gastroprotective activity.

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Antifertility Activity of Dictamnus albus Root Bark

  • Lee, Eun-Bang;Woo, Won-Sick;Kang, Sam-Sik;Shin, Kuk-Hyun;Chi, Hyung-Joon
    • 생약학회지
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    • 제17권2호
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    • pp.184-188
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    • 1986
  • The preliminary antifertility test of Dictamnus albus(Rutaceae) showed that a methanol extract of root bark decreased fertility in rats when administered orally on days $1{\sim}10$ postcoitum. Hexane, chloroform, butanol and aqueous fractions from the methanol extract, were tested to produce the result that only the hexane fraction exhibited positive activity. The hexane fraction was subfractionated into acidic, alkaloidal and neutral subtractions and tested. Neutral subtraction showed positive activity. From the neutral subtraction, fraxinellone was isolated as an active principle. The timed-dosing experiments revealed that antifertility activity of fraxinellone appeared to be exerted after tubal exit of the ova to prevent implantations.

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파워트레인 마운트계 설계를 위한 진동 이론 (Vibration Theory to Design Engine Mount System of Powertrain)

  • 원광민;윤희욱;방정환;강구태
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2000년도 춘계학술대회논문집
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    • pp.1907-1911
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    • 2000
  • In this paper, classical vibration theories are summarized to design engine mount system of passenger vehicles. The vibrational characteristics of powertrain system and its equation of motion are introduced. Based upon the equation, the concept of the center of gravity, the principle inertia axis, the elastic center, and the elastic axis are defined and some new concepts are suggested. The theory of mode decoupling and the relationship between TRA (Torque Roll Axis) and roll mode are also reexamined to support the design concept of engine mount systems.

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