• 제목/요약/키워드: R&D Lab.

검색결과 1,023건 처리시간 0.031초

반구형 LPCVD 다결정 실리콘 박막의 구조 및 특성 (Structure and Properties of Hemispherical Grain LPCVD Polycrystalline Silicon Films)

  • 박영진;전하응;이승석;이석희;우상호;김종철;박헌섭;천희곤;오계환
    • 한국재료학회지
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    • 제1권2호
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    • pp.77-85
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    • 1991
  • LPCVD(Low Pressure Chemical Vapor Deposition) System을 이용하여 여러가지 증착 변수에 따른 실리콘 박막의 표면형상에 대해 고찰하였다. 중착압력, 중착온도, 반응기체의 유속에 따라 증착층의 표면형상이 큰 변화를 나타냈으며, 증착압력과 반응기체의 유속이 증가할수록 유효면적이 최대가 되는 증착온도가 증가하였다. 이러한 실험결과는 안정한 핵의 생성률이 최대가 될때 유효표면적이 최대가 된다는 가정으로부터 유도된 식과 일치하는 결과를 나타냈다.

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A Study on the Evaluation Method of Perceptual Contrast with CIECAM02

  • Chong, Jong-Ho;Lee, Seung-Bae;Lee, Sang-Myung;Choi, Young-Chul;Bae, Jae-Woo;Kim, Hun-Soo;Chung, Ho-Kyoon
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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    • pp.1661-1663
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    • 2007
  • The contrast of display is one of the important specifications. Even if the contrast indicates luminance range which is a capability of the display and is greater in lower luminance or higher luminance, we consider that the greater contrast gets not the better performance. It is not the same value in human visual system. In practice, it is difficult to achieve the full dynamic range seen by human beings using electronic equipment. Therefore, we consider ambient condition and human perception to calculate perceptual contrast using the CIECAM02. In this paper, we propose perceptual contrast that is calculated using the brightness of CIECAM02.

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'제어모멘트자이로'의 질량불균형 보정 (The Imbalance Compensation in CMG)

  • 이종국;송태성;강정민;송덕기;권준범;서중보;오화석;전동익;홍영곤;이준용
    • 한국항공우주학회지
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    • 제48권11호
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    • pp.861-871
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    • 2020
  • '제어모멘트자이로' 내 모멘텀 휠의 속도가 커지게 되면 질량 불균형으로 인해 발생하는 의도하지 않은 힘과 토크가 증가하게 된다. 그리고 이러한 힘과 토크는 위성을 통해 촬영된 SAR 영상의 떨림을 유발하기 때문에 최소화하여야 한다. 본 논문에서는 '제어모멘트자이로' 내 모멘텀 휠의 질량불균형(정적질량불균형과 커플질량불균형)의 보상에 대해서 기술하였다. 우선 M&S를 통해 질량불균형의 발생에 따른 질량중심점에서 발생하는 힘과 토크의 발생을 예측하였다. 두 번째로는 힘과 토크의 측정 지점을 회전 중심에서 이격하였을 때, 질량불균형에 따른 힘과 토크의 발생을 예측하였다. 세 번째로는 질량불균형으로 인해 발생하는 힘과 토크를 측정하기 위한 장치 구성에 대해 기술하였으며, 네 번째로는 실제 구동하는 모멘텀 휠에 지정된 질량을 추가하였을 때, 힘과 토크의 변화량을 M&S와 비교하여 기술하였다. 그리고 마지막으로 이러한 분석을 바탕으로 24Nm급 '제어모멘트자이로'를 대기모드로 구동하였을 때의 보정 전과 후의 힘과 토크 변화를 기술하였다.

The Effects of a Mineral Supplement (Aquamin $F^{(R)}$) and Its Combination with Multi-Species Lactic Acid Bacteria (LAB) on Bone Accretion in an Ovariectomized Rat Model

  • Lee, Hyun-Gi;Lee, Tae-Hee;Kim, Jung-Ha;Seok, Ju-Won;Lee, Seung-Hoon;Kim, Yong-Hwan;Kim, Jin-Eung;Chung, Myung-Jun;Yeo, Moon-Hwan
    • 대한의생명과학회지
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    • 제16권4호
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    • pp.213-220
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    • 2010
  • Although an adequete intake of calcium (Ca) is recommended for the treatment and prevention of osteoporosis, the intake of Ca should be restricted because of its low rate of intestinal absorption. The purpose of this experiment was to identity the effect of the combined administration of Aquamin F (AQF) (a calcium agent) and lactic acid bacteria (LAB) on osteoporosis. Thirty ovariectomized (OVX) rats and six control rats were assigned to the following six groups, with six animals per group: sham Ca-deficient diet (Ca-D), OVX, LAB, AQF, and LAB-AQF. During the experiment, the body weight was measured; and after the experiment was completed, the serum biochemical analysis, the alkaline phosphatase, calcium, and inorganic phosphorus leves were measured. The tissue of the femur was stained and then scanned via CT. The body weight of the OVX group increased more significantly than that of the control group. The results of the bone mineral content (BMC), Bone mineral density (BMD), serum biochemical analysis and histological test on the femur epiphysis showed no difference between the OVX group and the LAB group, whereas the results of the AQF group were more significant than those of the OVX group. In particular, the LAB+AQF group showed more significant increases in the aforementioned results than the AQF group. This experiment showed that the combined administration of AQF and LAB in ovariectomized rats more significantly increased bone density than did a single administration of either AQF or LAB.

Comparative Studies of Molecular Mechanisms of Dopamine D2 and D3 Receptors for the Activation of Extracellular Signal Regulated Kinase 1/2 in HEK-293 cells

  • Cheong, Da-Woon;Cho, Choon-Sil;Kim, Hyun-Ju;Kim, Kyeong-Man
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.270.2-270.2
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    • 2002
  • Dopamine D2 and D3 receptors (D2R and D3R) belong to pharmacological D2R family and share similar structural and functional characteristics. Elucidation of their differential functional characteristics is important for understanding their roles in brain. ERK1/2 was chosen as an example of signaling component of D2R and D3R and systemic studies were conducted to understand the regulatory mechanisms on ERK1/2 activation. (omitted)

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