• Title/Summary/Keyword: V2C

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Studies on Availability of Components in Extract of Scutellariae Radix by Boiling water Method (전탕(煎湯)에 의한 황금(黃芩)의 성분(成分) 이행율(移行率)에 관한 연구(硏究) I)

  • Ko, Byoung-Seob;Joo, Hye-Jeong;Ma, Jin-Yeul;Park, Kap-Joo;Ahn, Sang-Woo
    • Korean Journal of Oriental Medicine
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    • v.2 no.1
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    • pp.496-505
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    • 1996
  • In order to improve the qualities of boiling extract the availability of standard compounds was investigated in extract of Scutellariae Radix. The standard compounds used baicalin(1), baicalein(2), and wogonin(3). The availabilities were analyzed by thin layer chromatography (TLC) and high performance liquid chromatography(HPLC) on $C_18$ column. The extract of RS-4(W/V=10g/100m1) showed the highest availabilities as 7.95% of baicalin(1), 1.04% of baicatein(2), and 0.31% of wogonin(3).

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Piezoelectric Microspeaker by Using Micromachining Technique (마이크로머시닝 기술을 이용한 압전형 마이크로스피커)

  • Suh, Kyong-Won;Yi, Seung-Hwan;Ryu, Kum-Pyo;Min, Nam-Ki
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.11a
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    • pp.45-46
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    • 2005
  • The piezoelectric ZnO thin films were deposited onto Al/Si substrate in order to figure out the crystalline and the residual stress of deposited films. As the $Ar/O_2$ gas ratio is increased, c-axis orientation of deposited films is significantly enhanced and also the residual stresses of ZnO films are all compressive. They are decreased from -1.2 GPa to -950 MPa as the $Ar/O_2$ gas ratio is increased. A diaphragm-based piezoelectric microspeaker fabricated on ONO films shows about 14 mPa output pressure at 1 kHz with $8V_{peak-to-peak}$.

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PRESENT AND FUTURE OF SUPER HIGH-EFFICIENCY TANDEM SOLAR CELLS

  • Yamaguchi, Masafumi
    • Electrical & Electronic Materials
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    • v.11 no.11
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    • pp.37-45
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    • 1998
  • In this paper, present status of super high-efficiency tandem solar cells has been reviewed and key issues for realizing super high-efficiency have also been discussed. In addition, the terretrial R&D activities of tandem cells, in the New Sunshine Program of MITI(Ministry of International Trade and Industry) and NEDO(New Energy and Industrial Technology Development Organization) in Japan are reviewed briefly. The mechanical stacked 3-junction cells of monolithically grown InGaP/GaAs 2-junction cells and InGaAs cells have reached the highest efficiency achieved in Japan of 33.3% at 1-sun AM1.5. This paper also reports high-efficiency InGaP/GaAs 2-junction solar cells with a world-record efficiency of 26.9% at AM0, 28$^{\circ}C$ and radiation damage recovery phenomena of the tandem cell performance due to minority-carrier injection under light illumination or forward bias, which causes defect annealing in InGaP top cells. Future prospects for realizing super-high efficiency and low-cost tandem solar cells are also described.

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Properties of the Electrodeless Discharge Lamp Using H-Discharge (H-방전을 이용한 무전극 방전 램프의 특성)

  • Kim, Tae-Hyoun;Park, Tong-Wha
    • Proceedings of the KIEE Conference
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    • 1998.07e
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    • pp.1708-1710
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    • 1998
  • In this study, several experiment is executed to analyze properties of Electrodeless Discharge Lamp using H-Discharge. 1. The operating frequency of this lamp is $2.45{\sim}2.65$[MHz] 2. The color of light is mild-white. And, it is shifted in the direction of red in low temperature. 3. In ambient temperature under $10^{\circ}C$, luminous efficiency is decreased precipitously. Therefore, research for improvement discharge-characteristic in low temperature need. 4. Discharge-characteristic stable between $160{\sim}240$[V]. And, luminous output is inverse proportion to coil-voltage. 5. When input-voltage is decreased continuously unstable section exist.

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LTPS 공정 Diode Laser Annealing 방식을 이용한 Poly-Si 결정화

  • Lee, Jun-Gi;Kim, Sang-Seop
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.336-336
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    • 2011
  • AMOLED에 대한 관심이 높아짐에 따라 LTPS (Low Temperature Poly Silicon) TFT에 대한 연구가 활발히 이루어지고 있다. 다결정 실리콘은 단결정 실리콘에 비해 100 cm2/V 이상의 이동도를 보이는 우수한 특성으로 인해 AMOLED 디스플레이에 적합하며 여러 기업에서 LTPS 공정을 이용한 TFT제작을 연구 중이다. LTPS 공정은 현재 ELA (Excimer Laser Annealing) 방식으로 대면적 유리기판에 ELA 방법을 적용함에 있어 설비투자 비용이 지나치게 높아진다는 단점을 가지고 있다. 설비투자 비용의 문제점을 해결하기 위해 Diode Laser을 이용하여 Annealing하는 방법에 대해 연구하였다. 본 연구는 Diode Laser Annealing 방식을 이용하여 poly-Si을 구현하였다. 단결정 실리콘을 제작하기 위해 ICP-CVD장비를 이용하여 150$^{\circ}C$에서 SiH4, He2 혼합, He/SiH4의 flow rate는 20/2[sccm], RF power는 400 W에서 700 W으로 가변, 증착 압력은 25mTorr으로 하였다. 940 nm 파장의 30 W Diode Laser를 8 mm Spot Size로 a-Si에 순간 조사하여 결정화, 그 결과 grain을 형성한 polycrystalline 구조를 확인하였다.

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Fabrication and Characterizations of Thick PZT Films for Micro Piezoelectric Devices (마이크로 압전 소자용 후막 PZT의 제조 및 물성 평가)

  • 박준식;박광범;윤대원;박효덕;강성군;최태훈;이낙규;나경환
    • Transactions of Materials Processing
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    • v.11 no.7
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    • pp.569-574
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    • 2002
  • Recently, thick PZT films are required for the cases of micro piezoelectric devices with high driving force, high breakdown voltage and high sensitivity, and so on. In this work, thick PZT films were fabricated by Sol-Gel multi-coating method. Microstructures, and electrical properties of films were investigated by XRD, FESEM, impedance analyzer, and P-E hysteresis. PZT films with 2.7$mu extrm{m}$ to 4.4${\mu}{\textrm}{m}$ thickness were fabricated. Dielectric constant, loss, remnant polarization and coercive field of them were 880~1650 at 1kHz, 2~3% at 1kHz, 26~32 $\mu$C/$ extrm{cm}^2$, and 33~60kV/cm, respectively. Also a transverse piezoelectric coefficient $(e_{31,f})$ measurement system was fabricated and tested for thick film samples.

우유와 쌀을 이용한 요구르트의 제조에 관한 연구

  • 홍외숙;고영태
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 2003.10a
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    • pp.216.3-217
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    • 2003
  • 본 연구에서는 우유에 탈지분유 또는 4종의 쌀을 각각 2%(w/v)첨가하여 커드상의 요구르트를 만들고, 대조군(우유로만 만든 요구르트)과 비교하여 쌀의 첨가가 젖산균의 산생성 및 커드상 요구르트의 품질(관능성, 저장성에 미치는 영향을 조사하였으며, HPLC를 이용하여 몇 가지 유기산을 분석하였다. 쌀의 첨가로 젖산균의 산생성이 대조군보다 촉진되었는데 현미의 촉진효과가 가장 현저하였다. 접종된 4종의 젖산균(Lacttobacillus 3종, Leuconostoc 1종) 중에서는 Lenc. mesenteroides 와 L. bulgaricus 의 산생성도가 높았다. HPLC에 의한 유기산 분석의 결과를 보면 우유나 2% 현미를 첨가한 우유에 L. bulgaricus를 접종하여 24시간 발효하는 동안 lactic acid 는 젖산균에 의해 생성되어 그 양이 현저하게 증가하였으나, 우유 중에 들어있는 citric acid 는 젖산균에 의해 이용되어 그 양이 현저히 감소하였다. 커드상 요구르트의 관능성은 쌀의 첨가로 표준시료보다 다소 저하되었으며, 쌀 첨가시료 중에서는 통일벼 참가시료가 다른 시료보다 우수하였다. 커드상의 요구르트를 2주일 간 5$^{\circ}C$냉장고에 저장하는 동안 산생성과 pH, 생균수에 거의 변화가 없어 저장성은 매우 우수한 것으로 나타났다.

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Fatigue Strength Assessment of TLP Tendon Porch Using API 2W Gr.50 Steel

  • Im, Sung-Woo;Seo, Young-Seok;Lee, Joo-Sung
    • Journal of Ship and Ocean Technology
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    • v.11 no.1
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    • pp.25-35
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    • 2007
  • This paper is concerned with the fatigue strength assessment of tendon porch found which is categorized as the special structural member in TLP. Large-scale tendon porch specimens have been designed and fabricated with API 2W Gr.50 steel recently produced by POSCO. Fatigue test has been carried out for three tendon porch specimens under various load level. Fatigue strength has been evaluated based on the nominal stress range and the results are compared with the fatigue design curve of DnV RP-C203. From the present experimental study, it has been found that the porch specimens satisfy the fatigue design rule although test was carried out under the positive stress ratio. It can be, therefore, said that the API 2W steel produced by POSCO possess sufficient fatigue strength.

Development of the high-temperature, high-pressure Dynamic pressure sensor with LGT (LGT를 이용한 고온, 고압용 동압 센서 개발)

  • Kwon, Hyuk Jae;Lee, Kyung Il;Kim, Dong Su;Kim, Young Deog;Lee, Young Tae
    • Journal of the Semiconductor & Display Technology
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    • v.11 no.2
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    • pp.17-21
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    • 2012
  • This study developed a high-temperature, high-pressure dynamic pressure sensor using LGT(lanthanum gallium tantalate). The sensitivity of the fabricated dynamic pressure sensor was 2.1 mV/kPa and its nonlinearity was 2.5%FS. We confirmed that the high-temperature dynamic pressure sensor operated stably in high-temperature environment at $500^{\circ}C$. The developed dynamic pressure sensor using LGT is expected to be applicable not only to gas turbines but also in various industrial areas in duding airplanes and power stations.

INTERACTIONS BETWEEN GALAXIES IN A LOW-REDSHIFT GROUP: THE NGC 4065 GROUP

  • TASUYA, ORARIK;SAWANGWIT, UTANE;KRIWATTANAWONG, WICHEAN
    • Publications of The Korean Astronomical Society
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    • v.30 no.2
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    • pp.465-467
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    • 2015
  • We presents a study of interactions between galaxies in the low-redshift group known as the NGC 4065 group. Imaging data were taken using the 2.4 meter telescope at the Thai National Observatory (TNO) for B, V and $R_c$ broadband filters and [$S\small{II}$] and Red-continuum narrowband filters. There are 21 galaxies in our sample. The results show that most early type galaxies (ETGs) with equivalent width EW($H{\alpha}$) < $10{\AA}$ are gas-deficient galaxies, while late type galaxies (LTGs) show more EW($H{\alpha}$) and are bluer than the ETGs. This means that star formation activity in the LTGs could be triggered by tidal interactions between galaxy members due to dense environmental effects in the compact group.