• 제목/요약/키워드: shin-huh

검색결과 522건 처리시간 0.027초

충남대학교 고고도 우주환경모사 진공설비의 구축 및 성능설험 (Development and Performance Test of Vacuum Facility at the CNU for High Altitude Space Environment Test)

  • 정성철;김연호;신강창;허환일
    • 한국추진공학회:학술대회논문집
    • /
    • 한국추진공학회 2007년도 제29회 추계학술대회논문집
    • /
    • pp.45-48
    • /
    • 2007
  • 마이크로 인공위성에 적용 가능한 마이크로 추력기를 개발하기 위해서는 고고도 환경을 모사할 수 있는 진공설비가 요구된다. 본 논문에서는 $10^{-5}$ torr의 진공도를 유지할 수 있는 진공설비를 구축하였고, 이 장비는 100${/sim}$120 km의 고도를 모사할 것으로 기대된다. 장치 선정 및 실제 장치 구축 후 진공도 성능 실험을 수행하였고 저진공 펌프를 작동시켜 마이크로 노즐의 성능 실험을 수행, 결과를 비교 분석하였다.

  • PDF

Structure-Activity Relationships of Gagaminine and Its Derivatives on the Inhibition of Hepatic Aldehyde Oxidase Activity and Lipid Peroxidation

  • Lee, Dong-Ung;Shin, Uk-Seob;Huh, Keun
    • Archives of Pharmacal Research
    • /
    • 제21권3호
    • /
    • pp.273-277
    • /
    • 1998
  • In order to determine the structure-activity relationships for antioxidative effects of gagaminine, a steroidal alkaloid isolated from the roots of Cynanchum wilfordi (Asclepiadaceae), two derivatives identified as sarcostin and penupogenin were prepared from gagaminine by hydrolysis and reduction. These compounds were evaluated for the inhibitory effects on the aidehyde oxidase activity and on lipid perbxidation in vitro. Furthermore, their effects were compared with those of gagaminine and the related compounds, cinnamic acid and nicotinic acid. The results of this study prove that the cinnamoyl group in the structure of gagaminine is critical in inhibition of the aldehyde oxidase activity while the nicotinoyl group may be necessary for anti-lipid peroxidation of the compound.

  • PDF

일반(一般)X선촬영(線撮影)에 있어서 편면(片面)시스템의 응용(應用) (An Application of Single Screen-Film System on General Radiography)

  • 박명환;조준석;송재관;허준;유장수
    • 대한방사선기술학회지:방사선기술과학
    • /
    • 제13권2호
    • /
    • pp.15-20
    • /
    • 1990
  • In clinical fields, single screen-film system will be generalized according to high speed and high image qualify of intensifying screen film system in future. In single screen-film system, for imaging the best image, we must choice good film according to speed and gredient. Double screen-film system will be replaced single screen film system in general radiography. Author has thought that single screen film system will be developed new diagnosis area according to X-Ray films.

  • PDF

금형 생산성 향상을 위한 금형 설계 시스템 개발 (Development of The Die & Mould-Design System for The Productivity Increase of Die and Mould)

  • 신장순;허영무;윤길상;김유진
    • 소성∙가공
    • /
    • 제14권3호
    • /
    • pp.239-244
    • /
    • 2005
  • The die & mould-design system fur the productivity increase is developed by our company. This system is made by UG API and constructs the standard through DB of parts of die & mould. Besides, the result of engineering analytic method is reflected in the design process in this system and the product precision is secured by On Machine Measurement method. Therefore, the ground of quality improvement and process innovation is solidified by the developed system and the competitiveness of die & mould manufacturing is intensified.

직류 전계 인가에 따른 절연유의 전하 축적 및 완화 현상에 관한 연구 (A Study on charge accumulation and relaxation phenomena by D.C energization in insulating oil)

  • 이창완;임헌찬;김용운;신태현;허창수;이덕출
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1996년도 하계학술대회 논문집 C
    • /
    • pp.1633-1635
    • /
    • 1996
  • This phenomena of streaming-electrification is generated between solid and liquid boundary called electric double-layer which is generated by potential difference. A charge separation at interfaces between a moving fluid and a solid boundary can give rise to the generation of substantial electric field and at last these can give rise ta insulating failure. Therefore injection of the adverse-charge in streaming-electrified insulating oil to eliminate the accumulation charge and its related phenomena was investigated.

  • PDF

중풍변증에 관련된 임상지식에 대한 요인분석 (A study of factor analysis for clinical knowledge about cerebrovascular diseases)

  • 권영규;박창국;강효신
    • 대한한의학회지
    • /
    • 제18권2호
    • /
    • pp.73-81
    • /
    • 1997
  • We have done factor analysis to study the effects of clinical knowledge on the diagnosis process. Clinical datas were made on 94 patients with cerebrovascular accident diagnosed by computed tomographic scan and who did not over 20 days after stroke. After analysis, totally 11 factors has been found. Among these factors, we interpreted significant 5 factors as oriental-medical meaning, Factor 1 meant Han-youl(寒熱) and factor 2 meant Huh-Shil(虛實). These were exactly corresponded with clinical experience.

  • PDF