• 제목/요약/키워드: Unit cell

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Analysis and Design of Low Pass Filter using Unit Cell based on CRLH Transmission Line

  • Yang, Lei;Yang, Doo-Yeong
    • International Journal of Contents
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    • 제8권3호
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    • pp.100-104
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    • 2012

  • In this paper, a unit cell for low pass filter design by using composite right and left-handed transmission line in conductor-backed coplanar waveguide is proposed. The characteristics of the unit cell are analyzed in order to design a low pass filter in small sizes. By changing the sizes of the unit cell, the parameters of right-handed and left-handed immittance components are changed and the desired characteristics of the unit cell are achieved. The equivalent circuit of the unit cell is extracted and analyzed either. As a result, the simulation results of the unit cell and the equivalent circuit are almost identified. The movement and energy distributions of electromagnetic field are shown to confirm the property of the unit cell. In the end, a low pass filter is demonstrated by cascading three proposed unit cells, which shows cutoff frequency of 1.53GHz and deep attenuation from 2.23GHz to 4.49GHz lower than -50dB.

  • https://doi.org/10.5392/IJoC.2012.8.3.100 인용 PDF KSCI

고체산화물연료전지용 대면적 단위전지 제조특성 및 성능평가 (Fabrication Characteristics and Performance Evaluation of a Large Unit Cell for Solid Oxide Fuel Cell)

  • 신유철;김영미;오익현;김호성;이무성;현상훈
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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    • pp.13-16
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    • 2008

  • Solid oxide fuel cell(SOFC) is an electrochemical energy conversion system with high efficiency and low-emission of pollution. In order to reduce the operating temperature of SOFC system under $800^{\circ}C$, the thickness reduction of YSZ electrolyte to be as thin as possible, e.g., less than 10 ${\mu}m$ are considered with the microstructure control and optimum design of unit cell. Methods for reducing the thickness of YSZ electrolyte have been investigated in coin cell. Moreover, a large unit cell($8cm{\times}8cm$) for SOFC was fabricated using an anode-supported electrolyte assembly with a thinner electrolyte layer, which was prepared by a tape casting method with a co-sintering technique. we studied the design factors such as active layer, electrolyte thickness, cathode composition, etc,. by the coin type of unit cell ahead of the fabrication process of a large unit cell and also reviewed about the evaluation technique of a large size unit cell such as interconnect design, sealing materials and current collector and so forth. Electrochemical evaluations of the unit cells, including measurements such as power density and impedance, were performed and analyzed. Maximum power density and polarization impedance of coin cell were 0.34W/$cm^2$ and $0.45{\Omega}cm^2$ at $800^{\circ}C$, respectively. However, Maxium power density of a large unit cell($5cm{\times}5cm$) decreased to 0.21W/$cm^2$ at $800^{\circ}C$ due to the increase of ohmic resistance. However, It was found that the potential value of a large unit cell loaded by 0.22A/$cm^2$ showed 0.76V at 100hrs without the degradation of unit cell.

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Pulsed laser depostion (PLD)법으로 증착된 $BaTiO_3/SrTiO_3$ 산화물 초격자의 성장 및 유전특성 (Growth and dielectric Properties or $BaTiO_3/SrTiO_3$ oxide artificial superlattice deposited by pulsed laser deposition (PLD))

  • 김주호;김이준;정동근;김용성;이재찬
    • 한국진공학회지
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    • 제11권3호
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    • pp.166-170
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    • 2002

  • $BaTiO_3$(BTO)/$SrTiO_3$(STO) 산화물 인공 초격자가 MgO(100) 단결정 기판위에 Pulsed laser deposition(PLD)법으로 증착되었다. 다층구조에서 BTO/STO 층의 적층 주기는 $BTO_{1\;unit\; cell}/STO_{1\;unit\; cell}$에서 $BTO_{125\;unit\; cell}/STO_{125 \;unit \;cell}$ 두께로 변화시켰고 초격자 전체 두께는 100 m으로 고정시켰다. X-ray 회절 결과는 다양한 주기의 BTO/STO 산화물 박막에서 초격자의 특성을 보였고 투과형 전자 현미경을 통해서 BTO와 STO의 두 층간의 계면에서 상호확산이 일어나지 않고 초격자가 잘 성장된 것을 확인하였다. 초격자의 유전율은 임계 두께 내에서 적층주기가 감소함에 따라 증가하였다. 이러한 초격자의 유전율은 낮은 주기 즉 $BTO_{2\;unit\; cell}/STO_{2\;unit\; cell}$ 주기에서 1230으로 높게 나왔으며 이러한 원인은 격자 변형(c/a ratio)에 기여된 것으로 분석되었다.

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DIETHYLSTILBESTROL (DES) INDUCES MORPHOLOGICAL ALTERATIONS IN OFFSPRING

  • MORITA Maki;SUGIMOTO Miki;TANAKA Takako;OKAMOTO Reika;IMANISHI Satoshi;MANABE Noboru;MIYAMOTO Hajime
    • 한국식품위생안전성학회:학술대회논문집
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    • 한국식품위생안전성학회 2001년도 The Asia-Pacific Conference on Reproductive Biology and Environmental Sciences
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    • pp.195-199
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    • 2001

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