• 제목/요약/키워드: Separation principle

검색결과 150건 처리시간 0.033초

강진향(降眞香)의 항암활성 성분 (Isolation of Antitumor Agent from the Heartwood of Dalbergia odorifera)

  • 박종대;이유희;백남인;김신일;안병준
    • 생약학회지
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    • 제26권4호
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    • pp.323-326
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    • 1995
  • Through bioassay-guided separation of the chemical constituents from the heartwood of Dalbergia odorifera, an 2'-O-methoxyisoliquiritigenin(1) was isolated as cytotoxic principle. 1 showed potent cytotoxic activity against the three kinds of human cancer cell lines (A-549, SK-MEL-2 and SK-OV-3) with similar activity to 5-Fluorouracil.

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가전기기용 교류 전동기 구동 시스템의 EMI 특성 및 필터 설계 (EMI Characteristics and filter design of AC Drives for Home Appliances)

  • 정세교;신휘범
    • 전력전자학회논문지
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    • 제9권1호
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    • pp.81-87
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    • 2004
  • 본 논문에서는 세탁기, 에어컨과 같은 가전기기에 사용되는 인버터 구동 교류 전동기 구동 시스템의 EMI 특성해석 및 필터 설계 방법에 대하여 기술하였다. 먼저, 인버터 구동 교류 전동기 구동 시스템의 전도성 EMI 발생 및 전달 메커니즘에 대하여 분석하였고, 공통 및 차동모드 노이즈 분리 기법을 이용한 EMI 필터의 설계 방법을 제시하였다. 제시된 방법의 타당성을 검증하기 위해 PWM 인버터로 구동되는 유도 전동기 구동 시스템에 대한 실험을 수행하였고 EN55014 EMI 기준을 만족하는 결과를 얻을 수 있었다.

비선형시스템의 관측기 제어기 조합 설계에 관한 연구 (A Study on the Design of Interlaced Controller-Observer for Nonlinear Systems)

  • 이춘근;양해원
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 B
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    • pp.682-684
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    • 1997
  • In the design of nonlinear control systems separation principle does not hold. Moreover even an exponentially decaying disturbances can destabilize a nonlinear system and lead to finite escape time from certain initial conditions. So we present a simple output feedback speed controller of induction motors which is designed to minimize the effects of observation error using the Kanellakopoulos et al's interlaced controller-observer design method. Simulation shows that the proposed controller has desired performance like another complex controllers.

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MF Membrane Application for Water Treatment in Japan

  • Okazaki, Minoru
    • 한국막학회:학술대회논문집
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    • 한국막학회 1995년도 추계 총회 및 학술발표회
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    • pp.80-93
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    • 1995
  • Membrane Technology, which has been in use for over twenty five years, has established itself as one of the principle separation methods. With improved technology, Reverse Osmosis ("RO") has been applied to large volume water treatment facilities. UF and MF Membrane Technology has, up until recently, been applied to small scale water treatment facilities. The fouling of membrane has restricted the growth of Membrane Technology in Water Treatment. Membrane fouling compound found in water causes the loss of flux across the membrane by absorbing to membrane and plugging their pores. Various methods have been used in the reduction and prevention of membrane fouling. For RO, a conventional pre-treatment system removes the pollutants, preventing the function decline of RO membrane by keeping SDI < 4 as the standard condition of feed water. UF and MF Membrane Technology that must have pre-treatment function within itself, are required to keep its ability not to be influenced by fouling.y fouling.

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창의적 문제 해결 기법의 물리적 모순 해결에 의한, 초절수형 양변기 시스템의 설계 (Design of Super Water-Saving Toilet System by Solving Physical Contradiction in Theory of Inventive Problem Solving (TRIZ))

  • 이홍석;이경원
    • 한국CDE학회논문집
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    • 제6권3호
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    • pp.193-197
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    • 2001
  • This paper describes the design process of super water-saving toilet bowl system by the theory of inventive problem solving (TRIZ). The physical contradiction in TRIZ is defined far saving water in toilet bowl system with preventing the bad smell from septic tank. The super water-saving toilet bowl system is obtained by using the separation principle in time far resolving the physical contradiction. The real system is made using CAD tools. The consumption of water in the system implemented, is estimated about 3 ιcomparing with 13 ι of that in conventional toilet bowl system.

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모드 분리 기법을 이용한 스위치 컨버터의 전도잡음 분석 및 대책에 관한 연구 (Study on the analysis and suppression of conducted noise from switching converter by the mode separation technique)

  • 김진성;권준혁;김양모
    • 전자공학회논문지S
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    • 제35S권4호
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    • pp.128-138
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    • 1998
  • This paper describes a principle of the conducted noise separator which can separate the conducted noise to the common mode and differential mode(normal mode), and presents the transfer characteristics of the separator designed and manufactured. We separated the conducted noise generated from switched mode converter to the CM and DM conducted noise, and also analyzed the source and path of conducted noise in the converter by the conducted noise separator. Since we could easily get the characteristics of the CM and DM conducted noise by the separator, we could efficiently determine the contermeasures for the reduction of the conducted noise and establish the foundation of the systematic procedure for the design of low pass filter.

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2차원 밀폐 캐비티의 고레이놀즈수 흐름에 관한 연구 (A Study on High Reynolds Number Flow in Two-Dimensional Closed Cavity)

  • 최민선;송치성;이영호
    • Journal of Advanced Marine Engineering and Technology
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    • 제20권3호
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    • pp.101-109
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    • 1996
  • Two-dimensional lid-driven closed flows within square cavity were studied numerically for four Reynolds numbers : $10^4$, 3$\times10^4$, 5$\times10^4$ and 7.5$\times10^4$. A convective difference scheme to maintain the same spatial accurary by irregular grid correction is adopted by applying the interior division principle. Grid number is $80\times80$and its minimum size is about 1/400 of the cavity height. At Re=$10^4$, periodic migration of small eddies appearing in corner separation region and its temporal sinusoidal fluctuation are represented. At three higher Reynolds numbers(3$\times10^4$, 5$\times10^4$ and 7.5$\times10^4$), an organizing structure of four consecutive vorticles at two lower corners is revealed from time-mean flow patterns. But, instantaneous flow characteristics show very random unsteady fluctuation mainly due to the interaction between rotating shed vortices and stationary eddies within the corners.

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Hydrogen Production by Photoelectrochemical Water Splitting

  • Seo, H.W.;Kim, J. S.
    • Applied Science and Convergence Technology
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    • 제27권4호
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    • pp.61-64
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    • 2018
  • The basic principle and concept for hydrogen production via water-splitting process are introduced. In particular, recent research activities and their progress in the photoelectrochemical water-splitting process are investigated. The material perspectives of semiconducting photocatalysts are considered from metal oxides, including titanium oxides, to carbon compounds and perovskites. Various structural configurations, from conventional photoanodes with metal cathodes to tandem and nanostructures, are also studied. The pros and cons of each are described in terms of light absorption, charge separation/photoexcited electron-hole pair recombinations and further solar-to-hydrogen efficiency. In this research, we attempt to provide a broad view of up-to-date research and development as well as, possibly, future directions in the photoelectrochemical water-splitting field.

탄소중립을 지향하는 전기화학적 이온 분리(EIONS) 기술 (Electrochemical Ion Separation Technology for Carbon Neutrality)

  • 주화주;안재욱;전성일;윤제용
    • 공업화학
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    • 제34권4호
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    • pp.331-346
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    • 2023
  • 탄소중립 달성을 위해 에너지 효율적이고 전기화된 사회에 직접 이용될 수 있는 친환경 공정이 주목받고 있다. 다량의 에너지를 소모하는 기존의 열 및 압력 기반의 담수화 기술에서도 이는 예외가 아니기에, 최근 차세대 전기화학 기반 담수화 기술들의 성장이 두드러진다. 대표적으로 에너지 저장 장치의 구동 원리를 기반으로 하는 전기화학적 이온 분리(electrochemical ion separation, EIONS) 기술이 있으며, 여기에는 축전식 탈염(CDI) 기술과 배터리 담수화 시스템(BD)가 포함된다. EIONS 기술에는 시스템 성능 향상을 위해 CDI와 BD를 기본으로 한 다양한 응용 시스템들이 개발되어 왔는데, 이러한 결과물들의 의미와 독창성을 배경지식 없이 한눈에 파악하기 매우 어렵다. 따라서 우리는 이 리뷰 논문에서 EIONS 연구에서의 지난 몇 년간의 기술적 진보와 시스템 개별 특성을 각 시스템의 구동원리, 연구 배경, 장단점을 중심으로 명확하고 구체적으로 설명하고자 한다. 아울러, EIONS의 미래 발전과 연구 방향을 설명하며 리뷰 논문을 마무리하겠다. 이 논문을 통해 EIONS 연구를 막 시작하는 연구자들이 EIONS의 연구 동향을 보다 쉽게 파악할 수 있을 것이다.

조선시대 상례행렬복식에 나타난 상징성에 관한 연구 (A Study on Meanings of Funeral ceremony costumes in Chosun Dynasty)

  • 최해율;이순원
    • 복식
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    • 제50권
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    • pp.119-128
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    • 2000
  • this study was designed to discuss the pattern of Confucian funeral ceremony and its costumes in Chosun dynasty thereby exploring the ideas and symbolic meanings expressed on them. 1. Male's official mourning dresses were composed of Choieui symbolizing sadness Choisang(최상), Dukun Sangkwan Sujil Yojil Kyodai and mourning stick Female's official mourning dresses consisted of Daersoojangkon and Kaedoo which were of simple kinds as compared to those of males. Duration of wearing mourning dreses was the longest to the death of father husband and eldest son The forms of mouring dresses were one and the same irrespective of the noble and the mean which expressed the sameness of the sorrow full of losting blood relative. Symbol expressed on funeral ceremony costumes were something like "eldestson-oriented" "male-centered" "distinction of the sexes" and "principle of yin and yang" to reinforce vitality to the costumes. 2. In the other funeral ceremony costumes in a royal fami8ly were those Euijangsu in red and blue colors Yeosakon in purple and white colors. Bandsman in Danryung and Guards in Kukonbok Changeui and Hoeui with five colors while the generally of people woere white dress in the ceremony Hoeui with five colors symbolized the principle of Yin and Yang costumes of military uniforms the dignity of the royal family: white dresses grife symbolizing the dignity of a royal family and Confucian sorrow as well 3. Unlike the mouring dresses there were great differences relative to socio-ecpmpomic status in funeral goods for dercoration Soyeo and daeyeo Among the goods the instrument to drive out evil spirites symbolized shamanism the distinction of Soyeo and Daeyeo separation of body and soul; the sculpture of the Lord of Hades and messenger philosophy of buddhistic netherworld: the engraving of blue and yellow dragons in bier and Juksanma the principles of Yin and Yang : elaborate burial accesaries realistic viewpoint of the hereafter.

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