• 제목/요약/키워드: LAE

검색결과 1,782건 처리시간 0.037초

통계적 접근을 통한 COMS 위성의 LAE 추력기 사용연료량 예측에 관한 연구

  • 박봉규;한조영;양군호;김방엽;박응식
    • 항공우주기술
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    • 제4권1호
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    • pp.95-102
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    • 2005
  • 본 논문은 2008년 발사예정인 한국의 통신해양기상위성에 대상으로 액체원지점엔진 발사 및 궤도획득에 사용되는 연료량 계산에 필요한 기술적인 접근에 대하여 기술하였고 그 계산 결과를 소개하였다. 발사체에 성능에 따른 전이궤도 진입오차 성분을 고려하기 위해여 통계적인 방법인 몬테칼로 시뮬레이션 기법을 사용하였다. 또한 통신해양기상위성에 고려 가능한 일부 발사체를 대상으로 표류궤도 진입 및 궤도획득에 요구되는 연료량을 계산하고 그 결과를 비교하였다.

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펨토초레이저를 이용한 금속 재료의 레이저 밀링 가공에 대한 연구 (Study on Laser Milling Process of Metal by Femtosecond Laser)

  • 강필식;박종인
    • 한국레이저가공학회지
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    • 제17권3호
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    • pp.10-14
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    • 2014
  • By the specific character of femtosecond laser controlled volume of magnitude of micrometer scale could be ablated without melting phase in SKD11 and SUS304. According to the laser machining parameters various sectional shapes could be engraved on the surface of metals. Typical engraved lines were $10{\mu}m$ wide and deep. Coarse-milled surface was made $10{\mu}m$ lower than the original elevation by a bunch of laser-engraved lines in suitable spacing. The repeated banks with a height of $10{\mu}m$ could be made with the combination of the intact area.

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Momordica charantia and Allium sativum : Broad Spectrum Antibacterial Activity

  • Khan, M.R.;Omoloso, A.D.
    • 생약학회지
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    • 제29권3호
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    • pp.155-158
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    • 1998
  • In the Asian sub-continent Momordica charantia and Allium sativum are extensively used as food and are popular in herbal medicine. The two were screened against 15 pathogens and both exhibited broard spectrum antimicrobial activity. As compared to the standard antibiotics, M. charantia demonstrated broader and higher level of activity against most of the organisms. On the other hand A. sativum showed comparable activity to the standard antibiotics. Both M. Charantia and A. sativum are proposed as non toxic, safe, broad spectrum antibacterial agents.

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The Vector Control of Induction Motor drives Speed Sensorless using a Fuzzy Algorithm

  • Seo, Young-Soo;Lee, Chun-Sang;Hwang, Lak-Hoon;Kim, Jong-Lae;Byong gon Jang;Kim, Joo-Lae;Cho, Moon-Tack;Park, Ki-Soo
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 ITC-CSCC -2
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    • pp.1013-1016
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    • 2000
  • In this study, the estimate speed of rotor in the induction motor with Model Reference Adaptive control System (MARC) principle and to study that vector control system feedbacks speed estimated to speed control system and its result is as follows; Considering with explanation an influence of speed estimation mechanism depend on error about the second resistance size established, it estimates the deviation of the second resistance establishment and exhibits a compensation method, what is more, it designs a reparation program using the fuzzy algorithm and testifies the result with the computer simulation. And besides, it composes the load torque estimation and estimates the load torque, as the result, feedback-compensating the result of estimation, it improves the efficiency. In consequence, it makes a good result for more powerful vector control system about the outside trouble.

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로보트를 위한 Dynamics 방정식의 해 유도와 Controller 설계에 관한 연구 (A Study on the Solution of Dynamics Equation and the Design of Controller for ROBOT)

  • 우상래;김형래;박인갑
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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    • pp.256-259
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    • 1987
  • In this paper, a servo controller for a robot manipulator is developed. It consists of a conventional MRAS controller for each joint together with a feedback control to Dynamics compensation. To generale the control torque effectively a currant drive method is adopted. The speed of the actuator is measured by using a tachometer and the position of the link is measured by using a potentiometer. To show the effectiveness of the proposed control algorithm the proposed controller is tested in real time.

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