• Title/Summary/Keyword: Seperation

검색결과 217건 처리시간 0.021초

Elastic Analysis of Plates Resting on Elastic Half-Space Considering the Local Segregation Between Plate and Foundation

  • Jinhwan-Cheung;Cho, Hyun-Yung
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1993년도 가을 학술발표회논문집
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    • pp.38-43
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    • 1993
  • It is one of classical problems in the elastic theory to analyze contact stresses between elastic bodies. Concrete pavements under traffic wheel loads can be considered as one of these typical problems. In this paper, an elastic plate resting on tensionless elastic half-space is analyzed by finite element method. The Boussinesq's solution of elastic half-space is used to evaluate the flexibility of foundation. One of the principal difficulties in solving the local seperation phenomena between plate and foundation is that the geometry of the system is unknown. To obtain the boundary of contact area, the flexibility matrix of foundation is modified after each cycle of analysis iteratively. Some numerical examples are presented by using these method.

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TRIZ를 활용한 클린룸용 저소음 및 저분진 케이블 이송 체인 시스템의 개발 (The Development of Cable Carrier Chain System with Low Noise and Dust for Moving Stages in Cleanrooms using TRIZ)

  • 김두진;현동훈;김영일
    • 반도체디스플레이기술학회지
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    • 제8권4호
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    • pp.83-88
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    • 2009
  • In this paper TRIZ was used to solve noise and dust reduction related to cable carrier chain system. On modern machines in a clean room, the contradictions arose due to increase noise and dust for the high speed were eliminated with 40 principles and seperation rules. As the results, the sound pressure level of the new carrier chain system was reduced to below 40 dB(A), and cleanroom classifications was satisfied with ISO class 4. In these successful results, TRIZ showed its usefulness in solving the design problems even with severe constraints.

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마이크로이멀젼을 이용한 유기오염물로 오염된 지반의 정화

  • 박기홍;권오정;박준범;이종문
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2002년도 추계학술발표회
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    • pp.175-178
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    • 2002
  • The purpose of this research is to evaluate the effect of microemulsion on the remediation of soil contaminated with organic materials. The laboratory tests were conducted to confirm the ability of microemulsion as remediation agent and compare remediation efficiency in microemulsion process with soil washing. In the test, pyrene was used as organic contaminant and alkylpolyethoxylates(C$_4$E$_1$) was used as surfactant. Microemulsion in the $C_4$E$_1$-water-decane mixture was formed in the range of 22 and 48$_{o}$ C at surfactant contents V=55%. Extraction was completed within 30 min and about 90% pyrene was removed. Seperation of pyrene with oil phase lowering temperature was sufficient for application in a multistep process.s.

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박리유동장에서 저속 익형의 공기역학적 성능해석 (An Aerodynamic Performance Analysis of the Low-Speed Airfoils in Seperated Flow Field)

  • 유능수
    • 산업기술연구
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    • 제15권
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    • pp.153-168
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    • 1995
  • The purpose of this study is to develop a method for predicting the aerodynamic performance of the subsonic airfoils in the 2-dimensional, steady and viscous flow. For this study, the airfoil geometry is specified by adopting the longest chord line system and by considering local surface curvature. In case of the inviscid-incompressible flow, the analysis is accomplished by the linearly varying strength vortex panel method and the Karman-Tsien correction law is applied for the inviscid-compressible flow analysis. The Goradia's integral method and the Truckenbrodt integral method are adopted for the boundary layer analysis of the laminar flow and the turbulent flow respectively. Viscous and inviscid solutions are converged by the Lockheed iterative calculating method using the equivalent airfoil geometry. And the analysis of the seperated flow is performed using the Dvorak and Maskew's method as the basic method. The wake effect is also considered and its geometry expressed by the formula of Summey & Smith when no seperation occurs. A computational efficiency is verified by the comparison of the computational results with experimental data and by the shorter execution time.

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한국 아동의 스트레스 대처행동 척도의 개발 (A Validity Study of an Instrument for Children's Stress Coping Behavior)

  • 윤종희
    • 가정과삶의질연구
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    • 제15권3호
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    • pp.95-106
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    • 1997
  • The purpose of this study was to develop an instrument which measures children's stress coping behaviors. The first 89 items were selected based on a literture review and a pilot study of 129 children with open questions. The final 75 items were selected using the data from subjects of 500 4th-5th and 6th grade children living in Seoul. The main study was conducted on March 5-10 1997. The data were analysis by frequencies percentages factor analysis and Cronbach's a. The resulting nine catagorical factors of 75 items in strument for children's stress coping behaviors were as fallows: positive revaluation of the situation emotional aggression problem-facing behavior information search for problem-solving emotion-vonvering behavior avoidance seeking spiritual support physical seperation for emotional relaxation emotional expression, The 9-factor 75-item scale explains 60.9% of children's stress coping behaviors and its value of Cronbach's a is 9.5.

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유교 상례복의 심리적 기능에관한 연구 (A Study on Psychological Function of Mourning Ceremonial Dresses in Confucianism)

  • 조우현
    • 대한가정학회지
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    • 제32권4호
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    • pp.233-240
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    • 1994
  • The purpose of this study is to consider psycological funtions of mourning dresses in Confucianism. By each step of A.V.Gennep's passage rites, the result of this thesis summarised as follow; In the first Seperation rites after calling the death' name three times the relatives for whom mourning is due become dishevelled hair bare feet and bare shoulder etc. In the second Transition rites, bereaved familly has worn 5 class mourning dresses in deep grief. In the third Cooperation rites, gradually the living familly goes through three year stages of changing mourning dresses to ordinary colthes. In Confucian funeral ceremony the deviation of clothing behavior in each mourning step sublimates bereaved person's sorrow into their internal security.

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시일의 마멸로 인한 다단터빈펌프의 위험속도 변화

  • 김영철;이동환;이봉주
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 1998년도 강연회 및 연구개발 발표회 논문집
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    • pp.203-209
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    • 1998
  • Rotordynamic analysis of a multistage turbine pump using finite element method is performed to investigate the effects of seal wear on Its system behavior. Stiffness and damping coefficients of the 2-axial grooved bearing are obtained as functions of rotating speed. Stiffness and damping coefficients of plane annular seals are calculated as functions of rotating speed as well as seal clearance. As the clearance of seals become larger, these stiffness and damping coefficients decrease drastically so that there can be significant changes in whirl natural frequencies and damping characteristics of the pump rotor system. Although a pump is designed to operate with a sufficient seperation margin from the 1st critical speed, seal wear due to long operation may cause a sudden increase in nitration amplitude by resonance shift and reduce seal damping capability.

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상호작용하는 부상화염의 특성에 관한 연구 (Characteristics of Interacting Lifted Flames)

  • 이승;이병준
    • 대한기계학회논문집B
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    • 제25권4호
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    • pp.461-466
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    • 2001
  • The characteristics of nonpremixed interacting flames are investigated in the parameter of nozzle configuration and nozzle separation distane, s. Three nozzle arrangements - diamond 4 nozzle, linear 5 nozzle and cross 5 nozzle- are used. When s is about 10 nozzle diameter, flames lift from the nozzle at the highest fuel flowrate compared with the other s cases. Normally flames are extinguished at the lifted states. Flowrates when blowout occurs are affected by the nozzle configuration, nozzle seperation distance. Blowout flowrates for the diamond- or cross-shaped nozzle cases are parabolic function of s. For 5 cross nozzle case, flames extinguished at 3.3 times higher flowrate than that of single equivalent area nozzle. Turbulent liftoff heights are not function of flowrates for these cases.

Gas Chromatography에 의한 잎담배와 담배연기응축물 중의 유기산 정량 (A Gas Chromatograpic Determination of Organic acids in Tobacco leaves and Cigarette Smoke Condensate)

  • 이문수;이운철;오세열;이규서
    • 한국연초학회지
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    • 제5권1호
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    • pp.67-72
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    • 1983
  • Gas Chromatography를 이용하여 잎담배와 연기응축물 중의 비휘발성유기산과 지방산을 정량 분석하였다. 특히 이들 유기산들은 단엽담배일 때 주류연으로 이행율을 조사하였는 바 linolenic acid, 31~62%, linoleic, 21~59% palmitic 29~38%, malic acid 4~6% 정도의 이행율을 보였다.

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