• 제목/요약/키워드: 이영식

검색결과 219건 처리시간 0.035초

한국 남해의 해황과 영양염 분포의 격월 변화

  • 최용규;김상우;이영식;성기탁;서영상
    • 한국환경과학회:학술대회논문집
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    • 한국환경과학회 2007년도 춘계 학술발표회 발표논문집
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    • pp.292-293
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    • 2007
  • 한국 남해안에서 2005년 10월부터 2006년 8월까지 격월별로 관측된 CTD 자료 및 분석된 영양염 자료를 가지고 격월별 해황 및 영양염의 분포를 살펴 보았다. 겨울철에는 표층과 저층간의 수직 혼합으로 일정한 수괴 분포 및 수온과 염분에 대해서 일정한 영양염 분포를 나타내었다. 그리고 연안역과 외양역 사이에 수온 전선이 뚜렷하였다. 그러나 여름철에는 양자강 저염수의 유입으로 T-S상에서 수형의 분포 범위가 넓었으며, 또한 수온과 염분에 대한 영양염의 분포도 일정하지 않았다. 그리고 여름철에는 저염수 유입에 의해서 수온 전선보다는 염분 전선이 뚜렷하였다. 봄과 가을에는 계절적 천이기로 수온과 염분의 분포에서 뚜렷한 pattern을 보이지 않았다.

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거대 행성들과 혜성들의 분광학 (SPECTROSCOPY OF PLANETS AND COMETS)

  • 김상준;이영식;이유;김용하
    • 천문학논총
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    • 제15권spc1호
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    • pp.31-38
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    • 2000
  • We have presented detected molecules, atoms, radicals, ions, and dimers in the atmospheres of planets and comets from Earth-based and spaceborne observatories during the last 3 decades. We have reviewed spectroscopic studies on the auroral emissions and air glows of the giant planets, and briefly summarized spectroscopic observations of dimers in the atmospheres of the giant planets and Titan. In particular, we highlighted the recent detections of new molecular emissions and absorptions in the spectra of the giant planets, Titan, and recent bright comets from spaceborne or ground-based observatories. We also reviewed current models and theories of the origin and evolution of the solar system, and implications of isotopic ratios in these atmospheres.

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IT 부품용 마그네슘 합금의 고속 탭핑가공에 관한 연구 (A Study on the High Speed Tapping of Magnesium Alloy for IT Parts)

  • 이상민;박휘근;이원석;김택수;채승수;이충석;백영종;조현택;이영식;이종찬
    • 한국기계가공학회지
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    • 제11권3호
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    • pp.29-34
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    • 2012
  • This paper reports some experimental results in high speed rigid tapping of magnesium alloy(AZ91D). M3 spiral tap and high speed spindle tapping center of gantry type were used in experiments and thrust forces were measured. The experimental results indicate that the thrust forces are proportional to the spindle speed and depth of cut. The thrust forces increase as the depth of cut increases. M3 Tapping was achieved at the spindle speed of 10,000rpm, depth of cut of 1.5D and total stroke of 32mm.

자동차 크랭크샤프트 멀티 연삭시스템의 구조해석에 관한 연구 (A Study on the Structural Analysis of Automotive Crankshaft Multi Grinding Machine)

  • 최윤서;이원석;황인환;박휘근;조현택;이영식;김기정;송순태;이종찬
    • 한국기계가공학회지
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    • 제11권1호
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    • pp.20-25
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    • 2012
  • A Crankshaft multi grinding machine is developed for manufacturing of high precision crankshaft. The grinding head part of the developed machine should be moved precisely during grinding of work materials. In this paper, structural and modal analysis for the crankshaft multi grinding machine is carried out to check the design criteria of the machine. The analysis is carried out by FEM simulation using the commercial software. The machine is modeled by placing proper shell and solid finite elements. The results of structural and modal analysis confirmed that the structural characteristics of grinding machine and the structural safety are considered secure.

Application of mid-infrared TDLAS to various small molecule diagnostics

  • 이영식
    • 천문학회보
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    • 제35권1호
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    • pp.25-25
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    • 2010
  • The spectroscopy over a region from 3 to 17 ${\mu}m$ based on the tuneable diode lasers (TDLAS) is the most powerful technique for in situ studies of the diagnostics of small molecules. The increasing interest in small molecules especially containing carbon, oxygen, hydrogen, and fluorine containing ones can be fulfilled by TDLAS at 0.0001 cm-1 resolution, because most of these compounds are infrared active. TDLAS provides a means of determining the absolute concentrations of the ground states of stable and transient molecular species, which can be employed for the time dependent studies in sub micro second scale. Information about gas temperature and population densities can also be derived from TDLAS measurements. Collisional energy transfer between the small molecules can be studied with TDLAS. Also, a variety of free radicals and molecular ions have been detected by TDLAS. Since plasmas with molecular feed gases are used in many applications, there are new applications in industrial field. Recently, the development of quantum cascade lasers (QCLs) offers an attractive new option for TDLAS.

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수차형 유회수기의 개발 (Development of Water Wheel Type Oil Skimmer)

  • 노준혁;박안진;강상훈;이영식;김종현;윤범상
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2000년도 추계학술대회 논문집
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    • pp.123-128
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    • 2000
  • The ocean is now increasingly suffering from pollution mainly caused by oil spill accidents roil increasing marine transportation. It cause not only the deterioration of ocean resources but also critical damage on the ocean ecosystem. Present study is an experimental one for the development of the oil skimmer which can collect spilled-oil actively and effectively from the sea surface. As an effort of achieving it, a new type of water wheel attached nil skimmer was devised, based upon the concept of orifice. The shapes of the water wheel, blades and oil storing tank are found to be very important factors on the oil skimming performance through systematic experimental analysis. Real oil recovery test was also carried out in square tank using the oil skimmer with their optimal shapes. Quite satisfactory result are obtained from the test which showed 99% and 98% recovery rates for light oil and heavy oil in still water condition, respectively.

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가막만해역의 Phosphatase 활성도 및 Kinetics

  • 김숙양;이영식;김상수;오현주;정창수;조민희;김병만;문성용
    • 한국환경과학회:학술대회논문집
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    • 한국환경과학회 2006년도 추계 학술발표회 발표논문집
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    • pp.301-303
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    • 2006
  • 조사해역에서의 Phosphatase에 의한 최대분해속도(Vmax)는 $0.26\;{\sim}\;7.09{\mu}M/L/hr$ 로서, 식물플랑크톤 bloom을 보였던 6월27일 조사 시에 높게 나타났으며 수온이 하강하고 클로로필 농도가 낮았던 9월13일 조사결과에서 가장 낮게 나타났다. 식물플랑크톤에 의한 유기 인산염 분해를 알아보기 위해 Specific activity를 구하였다. Phosphatase activity와 Chlorophyll. a의 변화는 유사한 변화를 보여주고 있으며, 이는 식물플랑크톤 이 Phosphatase의 분비에 큰 기여를 하는 것으로 나타났다.

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125[W]급 태양광 모듈로 구성된 독립형 태양광 시스템에 관한 연구 (A study on stand-alone photovoltaic system consisting of photovoltaic module of 125[W])

  • 황계호;이영식;윤종보;조인수;이봉섭;정도영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 제39회 하계학술대회
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    • pp.992-993
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    • 2008
  • 본 논문은 임의의 일사량 및 온도 등의 조건에 따라 태양전지의 출력특성을 전기적으로 시뮬레이션하여 여러 회사의 기존 제품 태양전지 모듈의 파라미터와 비교 검토하였고, 또한 이를 바탕으로 태양전지 모듈 어레이를 시뮬레이션하여 최적인 태양전지 모듈 어레이의 규모를 선택하여 독립형 태양광 시스템을 구현하였다.

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차량 승객 자동탐지를 위한 비젼시스템 (An Vision System for Automatic Detection of Vehicle Passenger)

  • 이영식;배철수
    • 한국정보통신학회논문지
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    • 제9권3호
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    • pp.622-626
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    • 2005
  • 본 논문은 지능형 교통시스템(intelligent transportation system)에 적용될 수 있는 방안으로써, 안정된 영상신호를 제공하여 자동으로 차량안의 승객을 탐지하는 시스템을 제안한다. 제안된 시스템은 높은 대역(upper-band)과 낮은 대역(lowe.-band)의 스펙트럼 강도를 조합하는 근적외선(Near-Infrared) 카메라를 이용하여 안정된 영상신호를 획득할 수 있었으며, 실험결과를 통해 제안된 방법의 효율성을 입증할 수 있었다.

한 측에서만 거칠기가 설치된 삼각덕트의 열전달과 압력강하 특성 (Heat Transfer and Pressure Drop Characteristics of Triangular Ducts with One Side Rib-Roughened)

  • 안수환;이영식;이병창
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집B
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    • pp.65-70
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    • 2000
  • Experimental investigations were conducted to study the forced convection of fully-developed turbulent f)on· in horizontal equilateral duct fabricated with the same length and equivalent diameter, but different surface roughness Pitch ratio(P/e) of 4, 8 and 16 on the one side wall only The experiments were performed with the hydraulic diameter based Reynolds number ranged from 70.000 to 10,000 The entire bottom wall of the duct was heated uniformly and the other surfaces were thermally insulated. To understand the mechanisms of the heat transfer enhancement. measurements of the heat transfer were done to investigate the contributive factor of heat transfer promotion. namely the fin effect. And the results were compared with those of Previous investigations for similarly configured channels, at which they were roughened by regularly spaced transverse ribs in the rectangular and circular channels.

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