• 상하수도학회지
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• 제27권5호
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• pp.547-554
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• 2013

Chlorine has strong oxidizing power, also it is many advantages over other disinfectants such as the residual characteristic and economic feasibility. However, chlorine also has disadvantages such as creating disinfection by-products of chlorine as THMs. In particular, the most deadly disadvantage of chlorine is that it is extremely poisonous toxins about all alive lives. Disinfection with electrolysis water can be a very useful way Because you do not have to worry about chlorine's dangerous. In this study, we evaluated the potential as a disinfectant, across the evaluating disinfection effect and generating characteristic of by-products. The electrolyzed water could be obtained removal efficiencies of over 99.9 % the coliform by operating condition such as residence time, current density (voltage), the electrode gap. The residual chlorine be generated 10,000 mg/L in current density $1.0A/dm^2$ and residence time of 10 minutes. The residual chlorine concentration was possible to maintain a stable. The by-products generated by high concentration residual chlorine in the reactor such as trihalomethanes, haloaceticacid, chloralhydrate, haloacetonitrile were detected in less than a water quality standards. At the concentration of less than residual chlorine of 1 ppm, the chlorine disinfection by-products be generated most below the detection limit.

• 조명전기설비학회논문지
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• 제16권3호
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• pp.74-83
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• 2002

본 논문은 전력설비에 조기적용이 예상되는 초전도한류기의 파라메타를 정의하고 앞으로 개발방향을 제시하기 위하여 한류기의 동작원리, 특성 및 계통조기적용가능성들을 근거로 파라메타의 특성을 비교 ·평가하였다. 또한 한류기의 계통적용효과를 분석하기 위하여 SFCL이 기간 특고압 모델계통에 도입한 경우를 상정하여 3선지락 고장에서 저항형과 유도형 SFCL의 도입 효과에 대하여 RTDS (Real Time Digital Simulation)/EMTDC(Electromagnetic Transient DC)로 시뮬레이션하였다. 특히 저항형과 유도형의 한류효과의 비교 평가, 모선전압의 저하 억제 및 계통과 한류기의 파라메타와의 관련성에 대하여 검토하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
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• pp.278-281
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• 2000

In this study, the electrical characteristics of 100V -Class LDMOSFET for high temperature applications such as electronic control systems of automobiles and motor driver were investigated. Measurement data are taken over wide range of temperature(300K-500K) and various drift region length(6.6$\mu\textrm{m}$-12.6$\mu\textrm{m}$). In high temperature condition(>450K), drain current decreased over 50％, and specific on-resistance increased about twice in comparison with room temperature. Moreover the ratio R$\sub$on//BV, a figure of merit of the device, increased with increasing temperature.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(2)
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• pp.13-16
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• 2002

In this study, the electrical characteristics of 100v-Class LDMOSFET for high temperature applicat -ions such as electronic control systems of automo -biles and motor driver were investigated. Measurement data are taken over wide range of temperature(300k-SOOK) and various gate length(1.5 #m-3.0#m, step 0.3). In high temperature condition(>500k), drain current decreased over 30%, and specific on- resistance increased about three times in comparison with room temperature. Moreover, the ratio ROJBV, a figure of merit of the device, increased with increasing temperature.

• 전자공학회논문지A
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• 제33A권5호
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• pp.85-93
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• 1996

The far-zone scattered field patterns of a hyperbolic reflector antenna are analyzed by using uniform geometrical theory of diffraction(UTD). The main objective of this paper is to obtain the higher order diffraction contributions which provide the continuity over the shadow boundaries of the first order solution. to obtain the scattered magnetic field characteristics, the scattered field components of the secodn-order diffraction, diffraction-reflection, diffraction-reflection-diffraction terms are added to the result of the previous research. The results of the present research are compared to those of the first order solution and the method of moments. One can observe the improvemtn of the current approach over the first order solution. also, the results of the present method agree very well with those of the moment methods especially in the transition regions near the first order diffraction shadow boundaries.

• 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.

• 설비공학논문집
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• 제20권3호
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• pp.197-204
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• 2008

DMFC(Direct Methanol Fuel Cell) is one of promising candidates for power sources of small mobile IT devices like notebook, cell phone, and so on. Efficient operation of fuel cell system is very important for long-sustained power supply because of limited fuel tank size. It is necessary to investigate operation characteristics of fuel cell stack for optimal control of DMFC system. The generated voltage was modeled according to various operating condition; methanol concentration, stack temperature, and load current. It is inevitable for methanol solution at anode to cross over to cathode through MEA(membrane electrode assembly), which reduces the system efficiency and increases fuel consumption. In this study, optimal operation conditions are proposed by analyzing stack performance model, cross-over phenomenon, and system efficiency.

• 대한전자공학회논문지
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• 제25권5호
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• pp.536-541
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• 1988

The push-pull current-fed DC-to-DC converter has only one energy storage reactor in series with the input for any number of outputs. It is considered that this property of the converter has considerable advantages over other multiple-output circuits. The steady state characteristics of the converter with two outputs is analyzed. It is known that the voltage difference between the two outputs appears by existing the 2nd winding resistance of transformer and there is a region of the duty ratio in which the voltage difference of the converter is smaller than that of the forward converter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1582-1584
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• 2004

The microstructure, electrical, and clamping voltage characteristics of ZPCCY-based varistor ceramics were investigated in the sintering time range of 1${\sim}$3 h. Increasing sintering time promoted the densification, in which the average grain size and density are increased in the range of $11.4{\sim}16.0{\mu}m$ and $5.34{\sim}5.54g/cm^3$, respectively. The nonlinear exponent decresed in the range of 60${\sim}$26 and the leakage current increased in the range of $1.3{\sim}10.7{\mu}A$ with increase of sintering time. The clamping voltage ratio was less than 2 for ratio surge current of 10 A over sintering times.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 센서 박막재료
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• pp.43-46
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• 2001

The ZnO devices using semiconductor properties, to include $MnO_2$, $Y_2O_3$ and other material, was fabricated by $Sb_2O_3$ mol ratio from 1 to 4 [mol%]. The non-linearity factor was calculated by setting current to be $1[mA/cm^2]$ and $10[mA/cm^2]$. The spinel structure was fonned by $Sb_2O_3$ addition and it was depressed the ZnO grain formation. The grain growing was controlled by spinel structure that has improved the non-linearity factors. The breakdown voltage characteristics of semiconductor devices to increase with $Sb_2O_3$ was increased in voltage-current. The non-linearity value of ZnO semiconductor devices was 45 over.