• 전기학회논문지
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• 제60권1호
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• pp.100-104
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• 2011

In this work, an optimum condition of electrolytes preparation for photovoltaic cells application was investigated experimentally in terms of impedance and conversion efficiency of the cells. 3-methoxyppropionitrie and redox pairs with LiI and $I_2$ were used as stable solvents for fabrication of electrolyte. Efficiency comparison of the prepared cells carried out for various additives and ionic liquids. From the results, there was an optimum concentration (about 0.3 M) of ionic liquids for efficient cell fabrication. For case of electrolyte using single DMAp additive, the maximum conversion efficiency of the cell was 6.4%($V_{oc}$: 0.78V, $J_{sc}$: 14.4 mA/$cm^2$, ff: 0.57). For case of electrolyte using both DMAp and CEMim additives, the maximum conversion efficiency of the cell was 7.2%($V_{oc}$: 0.79V, $J_{sc}$: 16 mA/$cm^2$, ff: 0.57). From the result of electrochemical impedance measurement, both Z1 and Z3 values of binary additives-based cell decreased compared to those of single additive-based. This is due to the decreased in internal and charge transfer resistivities of the cells.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 2000년도 추계공동학술대회논문집
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• pp.711-727
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• 2000

본 논문에서는 레이다 및 EW수신시스템에서 사용하는 SDLA를 5-7㎓(C-Band)의 RF 주파수대에서 설계 구현하였다. 구현한 SDLA의 특성은 -80㏈m-0㏈m의 동작범위를 얻었고, $\pm$1.2㏈이하의 대수오차, 19.2㎷/㏈의 대수기울기, 출력전압 범위는 0-l.53V, 2.0:1 이하의 VSWR, 약2㏈의 잡음지수와 900$\Omega$의 비디오 임피던스를 얻었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(2)
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• pp.201-204
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• 2001

LDMOSFET devices operated at low temperature have applications on satellite, space shuttle and low temperature system, etc. In this study, we measured the electrical characteristics of 100v Class LDMOSFET for low temperature application. Measurement data are taken over a wide range of temperatures (100K-300K) and various drift region lengths(6.6${\mu}{\textrm}{m}$, 8.4${\mu}{\textrm}{m}$, 12.6${\mu}{\textrm}{m}$). Maximum transconductance, $g_{m}$ and drain current at low temperatures(~100K) increased over about 260%, 50% respectively, in comparison with the data at room temperature. Breakdown voltage B $V_{ds}$, and specific on- resistance decreased. Besides, ratio $R_{on}$ BV, a figure of merit of the device, decreased with decreasing temperature.

• 한국정보통신학회논문지
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• 제8권6호
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• pp.1158-1165
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• 2004

본 논문에서는 802.11a 무선 근거리 통신망 (wireless LAN)에서 사용 가능한 5.25㎓ SiGe 저잡음 증폭기(LNA)를 제안한다. 본 저잡음 증폭기는 2단 구조로 1V의 공급전압에서 동작하며, 0.18$\mu\textrm{m}$ SiGe 공정으로 제작되었다. 이 저잡음 증폭기의 경우 5.25㎓의 동작주파수에서 17㏈의 전압이득, 2.7㏈의 잡음지수, -l5㏈의 반사계수, -5㏈md의 IIP3 및 -14㏈m의 1㏈ compression point와 같은 우수한 동작특성을 보였으며, 바이어스 회로에서 소모되는 0,5㎽를 포함하여 전체회로에서 소모되는 총 전력은 7㎽이다.

• 한국전기전자재료학회논문지
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• 제25권9호
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• pp.723-726
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• 2012

A current intensity convertible CLD chip was fabricated using small and large FET cell configuration. Pinch-off current of 8.82 mA and 11.56 mA were obtained for small and large cell in the CLD chip, respectively. Constant current was fairly maintained until the breakdown voltage of 60 V. Measured knee voltage, $V_k$ were 3.8 V and 4.5 V for small and large cell, respectively. We configured current amplifying chip with parallel connection of each cells, by connecting 8 individual large cells in parallel network, 92.0 mA of current was obtained. The pinch-off constant current of CLD chip was varied very linearly with respect to the number of parallel connected cell.

• The Korean Journal of Physiology and Pharmacology
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• 제1권6호
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• pp.741-748
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• 1997

In the present study, we have investigated the effect of metabolic inhibition on the inward rectifier K current ($I_{K1}$). Using whole cell patch clamp technique we applied voltage ramp from +80 mV to -140 mV at a holding potential of -30 mV and recorded the whole cell current in single ventricular myocytes isolated from the rabbit heart. The current-voltage relationship showed N-shape (a large inward current and little outward current with a negative slope) which is a characteristic of $I_{K1}$. Application of 0.2 mM dinitrophenol (DNP, an uncoupler of oxidative phosphorylation as a tool for chemical hypoxia) to the bathing solution with the pipette solution containing 5 mM ATP, produced a gradual increase of outward current followed by a gradual decrease of inward current with little change in the reversal potential (-80 mV). The increase of outward current was reversed by glibenclamide ($10\;{\mu}M$), suggesting that it is caused by the activation of $K_{ATP}$. When DNP and glibenclamide were applied at the same time or glibenclamide was pretreated, DNP produced same degree of reduction in the magnitude of the inward current. These results show that metabolic inhibition induces not only the increase of $K_{ATP}$ channel but also the decrease of $I_{K1}$. Perfusing the cell with ATP-free pipette solution induced the changes very similar to those observed using DNP. Long exposure of DNP (30 min) or ATP-free pipette solution produced a marked decrease of both inward and outward current with a significant change in the reversal potential. Above results suggest that the decrease of $I_{K1}$ may contribute to the depolarisation of membrane potential during metabolic inhibition.

• 한국멀티미디어학회논문지
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• 제6권1호
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• pp.161-166
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• 2003

본 논문에서는 블루투스에서 사용할 0.25$\mu\textrm{m}$ CMOS 공정을 이용한 고이득 저잡음 증폭기를 설계하였다. 설계한 저잡음 증폭기는 캐스코드 인버터를 이용하였으며, 레퍼런스 전압원을 가지고 쵸크 인덕터를 사용하지 않는 1단으로 설계하였다. 기존 1단으로 설계된 저잡음 증폭기의 10~15dB의 낮은 전력이득을 개선한 구조이다. 설계된 2.4GHz 저잡음 증폭기는 2.2dB의 NF값과 21dB의 높은 전력이득을 가지고 있으며, 2.5V 공급 전원에서 255mW 소모전력을 갖는다

• 대한화학회지
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• 제32권4호
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• pp.323-332
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• 1988

요소는 박테리아가 가지고 있는 urease에 의해 2분자의 $NH_3$와 1분자의 $CO_2$ 기체를 생성한다. Proteus vulgaris를 $NH_3\;와\;CO_2$ 기체 감응전극에 고정시켜 박테리아 전극을 조립하고, pH, 온도, 완충용액, 박테리아(균)의 양 및 여러가지 방해불질의 영향과 전극의 수명등에 관하여 조사하였다. $NH_{3-}$박테리아 전극은 $25^{\circ}C$에서 pH 7.4인 0.05M phosphate완충용액을 사용하였을 때 직선범위는 $7.0{\times}10^{-4}\;-\;3.0{\times}10^{-2}$M 이었고, 감응 기울기는 116.7 mV/decade였다. 한편, $CO_{2-}$박테리아 전극은 $30^{\circ}C$, pH 7.0, 0.1M phosphate완충용액을 사용하였을 때 $7.0{\times}10^{-4}\;-\;5. 0{\times}10^{-2}$M내에서 감응 기울기는 $45.4{\sim}45.7mV/decade$로 나타났다. 실제 임상적인 응용으로서 요속에 들어 있는 요소를 정량하고 분광광도법과 비교하였다. 결과적으로 이 전극의 경우는 실험과정이 간단하고 편리하여 신속하게 많은 양의 시료 분석이 가능하였다.

• 전기학회논문지
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• 제58권12호
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• pp.2474-2479
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• 2009

This paper presents an atmospheric microplasma-jet device for bio~medical application. The microplasma-jet device consists of four components; a thin Ni anode, porous alumina insulator, a stainless steel cathode and an aluminum case. The anode has 8 holes, and hole diameter and depth are $200 {\mu}m$ and $60 {\mu}m$, respectively. The discharge test was performed in atmospheric pressure using nitrogen gas and AC voltage at the optimum gas flow rate of 4 Vmin. The plasma-jet is ejected stably for the input voltage ranging from 5.5 to $9.5 kV_{p-p}$. The plasma becomes dense as the input voltage increases, which was verified by the hydrophilicity change of PMMA surface treated by the plasma. The temperature increasement of the aluminum film exposed to plasma-jet illustrates that the micro plasma-jet device is feasible for bio-medical application.

• Kyungpook Mathematical Journal
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• 제56권2호
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• pp.397-408
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• 2016

Let R be a 2-torsion free prime ring with center Z, U be the Utumi quotient ring, Q be the Martindale quotient ring of R, d be a derivation of R and L be a Lie ideal of R. If $d(uv)^n=d(u)^md(v)^l$ or $d(uv)^n=d(v)^ld(u)^m$ for all $u,v{\in}L$, where m, n, l are xed positive integers, then $L{\subseteq}Z$. We also examine the case when R is a semiprime ring. Finally, as an application we apply our result to the continuous derivations on non-commutative Banach algebras. This result simultaneously generalizes a number of results in the literature.