• Title/Summary/Keyword: 차단막

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Electrical properties of ZnO transparent conducting film fabricated by the sputtering method (스퍼터링법에 의한 ZnO 투명전도막의 제작과 전기적 특성)

  • Jeong, Woon-Jo;Cho, Jae-Cheol;Jeong, Yong-Kun;Yoo, Yong-Tek
    • Journal of Sensor Science and Technology
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    • v.6 no.1
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    • pp.49-55
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    • 1997
  • ZnO thin film had been deposited on the glass by sputtering method, and investigated by optical and electrical properties. When the rf power was 180W and sputtering pressure was $1{\times}10^{-3}$Torr at room temperature, thin lam deposited had strongly oriented c-axis and the lowest resistivity($1{\times}10^{-4}{\Omega}{\cdot}cm$), and then carrier concentration and Hall mobility were $6.27{\times}10^{20}cm^{-3}$ and $22.04cm^{2}/V{\cdot}s$, respectively. Transmittance of ZnO thin film in visible range was above 90%, and this thin film cut of the ultraviolet range below 320nm and the infrared range above 850nm. And after annealing in hydrogen atmosphere, the resistivity of ZnO thin film was somewhat decreased, while obtained as stable state.

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Functional Nanochannels to Control Ion Transportation with Monomolecule Selectivity (단일 이온 인식형 이송 제어 기능성 나노채널 기술)

  • Kim, Jeong Hwan;Lee, Eung-Sug;Whang, Kyung-Hyun;Yoo, Yeong-Eun;Yoon, Jae-Sung
    • Transactions of the KSME C: Technology and Education
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    • v.3 no.4
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    • pp.249-255
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    • 2015
  • Functional nanochannels were fabricated in order to control selective ion transportation with high permeability and low energy consumption. In this research, nanochannel platform fabrication process and surface functionalization process were developed. In addition, selective ion transportation and concentration measurement system was also set-up. By using fabricated multilayer metal membrane with electrical bias, 95% of ion ($Cl^-$) was blocked. This developed process is new-conceptional membrane fabrication technology and is expected to be applied to next-generation water purification/desalination, portable artifical kidney, and artificial sense organ.

Analysis the Effects of Curtain Weir on the Control of Algal Bloom according to Installation Location in Daecheong Reservoir (대청호 수류차단막 설치 위치에 따른 녹조제어 효과 분석)

  • Lee, Heung Soo;Chung, Se Woong;Jeong, Hee Young;Min, Byeong Hwan
    • Journal of Korean Society on Water Environment
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    • v.26 no.2
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    • pp.231-242
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    • 2010
  • The objective of study was to determine an optimal location of a float-type curtain weir in Daecheong Reservoir and to assess its effectiveness for the control of algal blooms in the reservoir. CE-QUAL-W2, a laterally averaged two-dimensional hydrodynamic and eutrophication model, was modified to accommodate vertical displacement of the weir according to water surface fluctuation and applied to simulate the reservoir hydrodynamics and water quality changes for the reservoir. The model calibrated in a previous study was updated and validated for different hydrological conditions representing drought year (2008) and normal year (2006) for the study, and adequately simulated the temporal and spatial variations of water temperature, nutrients and algal (Chl-a) concentrations. The effectiveness of curtain weir on the control of algal bloom was evaluated by applying the validated model to 2001 and 2006 assuming 9 scenarios for different installation locations. The reduction rates of algal concentration were placed in the range of 11.2~40.3% and 20.3~56.7% for 2001 and 2006, respectively. Although, the performance of curtain weir was slightly varied for different locations and different hydrological years, overall, the performance was improved as the weir was installed further downstream.

A Study on Copyright Protection Method of Web Image Contents (웹 이미지 콘텐츠 저작권보호 방법에 관한 연구)

  • Yi, Yeong-Hun;Cho, Man-Gi;Cho, Seong-Hwan
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.1
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    • pp.37-43
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    • 2015
  • Technical treatments of image contents on the web include the copy protection method such as the image capture protection technology and the traitor tracing method to detect unauthorized duplications through watermarking insertion or feature information technology. However, these two methods have their own weaknesses. The image capture protection method is unable to protect illegal captures when the URLs of image sources are exposed. The traitor tracing method is fundamentally unable to protect illegal captures due to its post-treatment method. Besides, the weakness of using the copyright information display technology involves easy removal of copyright information from copyrighted contents. This paper suggests a model of the web image contents protection system which makes it hard to separate copyright information from web image contents and allows image contents to be shown only in the authorized websites.

Seepage Behavior of Sea Dyke Final Closure with Installation of Bottom Protection Filter Mat (근고공 필터매트 설치에 따른 방조제 끝막이구간의 침투거동)

  • Oh, Young-In;Yoo, Jeon-Yong;Kim, Hyun-Tae
    • Journal of the Korean Geosynthetics Society
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    • v.5 no.1
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    • pp.25-32
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    • 2006
  • Sea dyke construction is simply defined as a cutting procedure of sea water flow. Sea dyke construction is more difficult than in-land construction because it is placed on deep seabed and exposed sea wave attack. Especially, the final closure of sea dyke is most dangerous due to the fast velocity of tidal flow. The final closure is consisted with vast rubble and heavy stone gabion, therefore the discharge velocity at land side of final close section is irregularly and sometime occur the fast discharge velocity. In this paper, the seepage model test performed to evaluate seepage behavior of final closure and continuous sea dyke section such as discharge velocity, hydraulic gradient, and phreatic line with installation of bottom protection filter mat. Based on the seepage model test results, the maximum discharge velocity of final closure section is 1.7m/sec and the discharge velocity is decreased maximum 23.7% with installation of bottom protection filter mat.

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Effects of Calcium on Nitric oxide (NO)-induced Adventitious Rooting Process in Radish (Raphanus sativus L.) Cotyledons (무 (Raphanus sativus L.) 자엽에서 산화질소 (Nitric oxide)에 의해 유도된 부정근 형성과정에 대한 칼슘의 효과)

  • Jin, Chang-Duck
    • Journal of Plant Biotechnology
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    • v.34 no.3
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    • pp.213-221
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    • 2007
  • The treatment of radish cotyledons with a nitric oxide (NO)-releasing substance, sodium nitroprusside (SNP) resulted in an increased adventitious root development in a dose-dependent manner. However, this NO-mediated enhancement effect was reversed when either 0.5 mM EGTA (an extracellular $Ca^{2+}$ chelator) or 0.1 mM $LaCl_3$ (a calcium channel blocker) was applied with $50\;{\mu}M$ SNP. Our results also showed that guaiacol peroxidase (GPX) and syringaldazine peroxidase (SPX) activities, which are known to play a key role in rooting, were more largely increased during adventitious root induction in the cotyledons treated with SNP. However, the treatment of cotyledons with SNP plus $LaCl_3$ inhibited the SNP-induced increases in the activities of both GPX and SPX. Trifluoperazine (TFP), an antagonist of calmodulin (a specific calcium-binding protein), also delayed adventitious root formation and significantly reduced the root length and number of the SNP-treated cotyledons as well as the deactivation of GPX and SPX enzymes. In conclusion, our results suggest that calcium is involved in the NO response leading to induction of adventitious root through a regulation of GPX and SPX.

Amiodarone-Induced ARDS after MVR -A case report- (승모판치환술 후에 발생한 아미오다론에 의한 급성호흡곤란증훈군 -1례 보고-)

  • 이기복;김응중;지현근;신윤철
    • Journal of Chest Surgery
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    • v.35 no.8
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    • pp.594-598
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    • 2002
  • Amiodarone is an iodinated benzofuran derivative that has been proved effective in the control of supraventricular and ventricular arrhythmias refractory to other antiarrhythmic drugs. In patients treated with amiodarone, subsequent surgical intervention is a common clinical scenario, but unfortunately we do not have definite data about complications due to amiodarone after cardiac surgery. Some reports have shown that amiodarone treatment can be associated with a state of $\alpha$-adrenergic and $\beta$-adrenergic receptor blockade, which requires more pacing and epinephrine infusion for perioperative hemodynamic support. And some reports have also identified a severe form of ARDS in patients on amiodarone therapy which was associated with siginificant morbidity and mortality. We exprienced a patient who expired after mitral valve replacement due to amiodarone-induced ARDS; therefore, we report this case with a brief literature.

Numerical Study on the Sealing Safety of a Valve Packing in a LPG Cylinder (LPG 용기용 밸브패킹의 누설안전에 관한 수치적 연구)

  • Kim, Chung-Kyun;Kim, Tae-Hwan
    • Journal of the Korean Institute of Gas
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    • v.11 no.1 s.34
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    • pp.34-39
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    • 2007
  • In this paper, the FEM result has been presented for a sealing safety between a valve packing and a valve seat during a open and close operation in a LPG cylinder. The sealing operation of a LPG valve is completed when the valve packing in which is made by a nylon-66 polymer is to stop a LP gas flow, which flows out from the outlet of a brass pipe in a LPG cylinder. The contact sealing mechanism of the valve may be classified by a flat contact of an unused valve packing and a circular groove contact of an used valve packing in a current LPG valve. Based on the FEM and experimental investigations the sealing force, 4.9 MPa for a flat contact mode of the unused valve packing is a little high compared to that of the used valve packing, which shows a circular groove contact geometry against a valve seat. But these sealing pressures for two contact modes are very low compared to the ultimate strenath 83 MPa of the nylon-66 and this may be designed with a excess strength of the valve.

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Analysis of Dimension Dependent Subthreshold Swing for FinFET Under 20nm (20nm이하 FinFET의 크기변화에 따른 서브문턱스윙분석)

  • Jung, Hak-Kee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.10
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    • pp.1815-1821
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    • 2006
  • In this paper, the subthreshold swing has been analyzed for FinFET under channel length of 20nm. The analytical current model has been developed , including thermionic current and tunneling current models. The potential distribution by Poisson equation and carrier distribution by Maxwell-Boltzman statistics are used to calculate thermionic emission current and WKB(Wentzel-Kramers-Brillouin) approximation to tunneling current. The cutoff current is obtained by simple adding two currents since two current is independent. The subthreshold swings by this model are compared with those by two dimensional simulation and two values agree well. Since the tunneling current increases especially under channel length of 10nm, the characteristics of subthreshold swing is degraded. The channel and gate oxide thickness have to be fabricated as am as possible to decrease this short channel effects, and this process has to be developed. The subthreshold swings as a function of channel doping concentrations are obtained. Note that subthreshold swings are resultly constant at low doping concentration.

Dependence of Drain Induced Barrier Lowering for Ratio of Channel Length vs. Thickness of Asymmetric Double Gate MOSFET (비대칭 DGMOSFET에서 채널길이와 두께 비에 따른 DIBL 의존성 분석)

  • Jung, Hakkee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.6
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    • pp.1399-1404
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    • 2015
  • This paper analyzed the phenomenon of drain induced barrier lowering(DIBL) for the ratio of channel length vs. thickness of asymmetric double gate(DG) MOSFET. DIBL, the important secondary effect, is occurred for short channel MOSFET in which drain voltage influences on potential barrier height of source, and significantly affects on transistor characteristics such as threshold voltage movement. The series potential distribution is derived from Poisson's equation to analyze DIBL, and threshold voltage is defined by top gate voltage of asymmetric DGMOSFET in case the off current is 10-7 A/m. Since asymmetric DGMOSFET has the advantage that channel length and channel thickness can significantly minimize, and short channel effects reduce, DIBL is investigated for the ratio of channel length vs. thickness in this study. As a results, DIBL is greatly influenced by the ratio of channel length vs. thickness. We also know DIBL is greatly changed for bottom gate voltage, top/bottom gate oxide thickness and channel doping concentration.