• 대한전기학회논문지
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• 제36권7호
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• pp.462-469
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• 1987

A metal gate MOSFET with source/drain regions self-aligned to gate region is proposed. The proposed MOS transistor is fabricated by utilizing the higher oxidation rate of source/drain regions with high doping concentration when compared with channel region with moderate doping. The thick oxide on the source/drain regions reduces the gate and drain(source) overlap capacitance down to that of a self-aligned polysilicon gate device while allowing the use of a metal gate with much lower resistivity than the more commonly used polycrystalline silicon. A ring oscillator composed of 15 inverter stages has been computer simulated using SPICE. The results of the simulation show good agreement with experimental measurement confirming the fast switching speed of propesed MOSFET.

• 한국자동차공학회논문집
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• 제5권2호
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• pp.173-182
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• 1997

The instantaneous flame temperature and soot formation and oxidation in a D. I. diesel engine are measured by using a two-color method. The proposed method based on the continuous spectral radiation from the soot particles in flames is applicable to industrial diesel engines without major modifications of their main characteristics. Measurements are performed at one location inside the combustion chamber of a D.I. diesel engine. Effects of different engine speeds and loads on flame temperature and KL factor which is an index of soot concentrations were examined. A little temperature change were observed with increasing engine speed, while increased with loads. The higher the flame temperature is, the lower the KL factor is.

• 한국분말재료학회지
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• 제19권4호
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• pp.297-303
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• 2012

In this study, voltammetry system for realizing high sensitivity nano-labeled sensor of detecting heavy metals was designed, and optimal system operating conditions were determined. High precision digital to analog converter (DAC) circuit was designed to control applied unit voltage at working electrode and analog to digital converter (ADC) circuit was designed to measure the current range of $0.1{\sim}1000{\mu}A$ at counter electrode. Main control unit (MCU) circuit for controlling voltammetry system with 150 MHz clock speed, main memory circuit for the mathematical operation processing of the measured current value and independent power circuit for analog/digital circuit parts to reduce various noise were designed. From result of voltammetry system operation, oxidation current peaks which are proportional to the concentrations of Zn, Cd and Pb ions were found at each oxidation potential with high precision.

• Composites Research
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• 제33권4호
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• pp.205-212
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• 2020

본 연구에서는 기상화학반응공정을 이용하여 실리콘카바이드가 코팅된 2종형상의 탄소/탄소복합재 위에 진공플라즈마용사를이용하여 하프늄카바이드를 코팅하였다. 코팅 전/후 시편을 5.06 MW/㎡의 열유속에서 120초 동안 산화 및 삭마 실험을 진행하였다. 시험 전/후의 질량 변화량을 통해 질량삭마율을 계산하였고 캘리퍼스와 고속카메라를 이용하여 길이변화를 측정하여 길이삭마량을 계산하였다. 시편 단면의 FE-SEM 및 EDS 분석을 통해 산화 및 삭마거동을 관찰하였다. 플라즈마 풍동 시험결과 코팅된 시편이 무게감소 및 길이변화가 적어 내산화 및 내삭마성이 높은 것으로 판단되었다. 그러나 동일조건에서 시험한 반구형과 원통형의 산화 및 삭마정도는 상이하였고 원통형에서 더 높은 내산화 및 내삭마성을 가지는 것으로 평가되었다.

• 전자공학회논문지A
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• 제33A권5호
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• pp.108-116
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• 1996

A semiconductor process imulator operated in windows$^{TM}$ environment has been developed. two-dimensional process simulation in personal computer has been enabled due to the improvement of CPU speed and the efficient use of memory. The process simulator in this paper is capable of calculating diffusion, oxidation, ion implantation, etching and deposition in two-dimensional manner. In addition, graphic-user-friendly editor, parser, and multi-dimensional graphical routine is also available in the devloped simulator.

• Journal of Advanced Marine Engineering and Technology
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• 제23권6호
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• pp.755-760
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• 1999

To remove nitrogen oxides(NOx) in exhaust gas of diesel engine three-way catalytic process with plasma discharger has great possibilities. Characteristics of NOx removal depends on NO conver-sion to $NO_2$ and /or $HNO_3$ due to high activation energies for NO oxidation and reduction, NOx removal efficiency by using three-way catalytic with plasma discharger indicated about 50% at 40watt power consumption condition.

• 한국생산제조학회지
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• 제19권2호
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• pp.295-300
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• 2010

Inconel 718 alloy, widely used as material of aircraft engine, has a good mechanical property in high temperature, strong anti-oxidation characteristics in oxidated current over $900^{\circ}C$, and also is not easily digested in the air containing sulfur, therefore, its usage as mechanical component is expanding rapidly. Even though Inconel alloy 718 is difficult to machine, it requires highly precise processing/machining to sustain its component quality of high accuracy. In this paper, general turning operation conditions arc tested to select the best cutting process condition by measuring surface roughness through implementing experiments with orthogonal array of cutting speed, feeding speed and cutting depth as processing parameters based on the Taguchi method. Optimal turning operation conditions are extracted from the proposed experimental models.

• 한국기계가공학회지
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• 제8권4호
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• pp.48-53
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• 2009

Inconel 718 alloy, widely used as material of aircraft engine, has a good mechanical property in high temperature, strong anti-oxidation characteristics in oxidated current over $900^{\circ}C$, and also is not easily digested in the air containing sulfur, therefore, its usage as mechanical component is expanding rapidly. Even though Inconel alloy 718 is difficult to machine, it requires highly precise processing/machining to sustain its component quality of high accuracy. In this paper, general turning operation conditions are tested to select the best cutting process condition by measuring surface roughness through implementing experiments with orthogonal array of cutting speed, feeding speed and cutting depth as processing parameters based on the Taguchi method. Optimal turning operation conditions are extracted from the proposed experimental models.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.24-25
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• 2006

High-Speed Centrifugal Compaction Process is one of slip-using compacting method originally developed for processing of oxide ceramics. In this study, we apply the HCP to ultra-fine (0.1 micron) WC powder. Organic liquid of heptane was chosen as dispersing media to avoid possible oxidation of WC. The mixing apparatus was a key to obtain dense compacts. Only the slips mixed by high energy planetary ball mill were packed up to 55% by the HCP, and sintered to almost full density at 1673 K without any sintering aids. This sintered compact marked Vickers hardness of Hv 2750 at maximum.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.311-320
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• 2009

Most advanced countries are researching to apply light weight materials far rolling stock because weight reduction for railway body derives cost-saving, energy-saving, and high-speed. Likewise, current Korea rolling stock field makes arduous effects of weight-reduction, miniaturization, and high-efficiency to achieve a high-speed railway. Aluminum becomes suitable material for these projects because it is much lighter than steel or stainless. Manufacturing the railway car body by using the Aluminum is increasing because Aluminum is not bringing the corrosion by unique oxidation-passivate. Aluminum extrusion profile far railway body requires a high mechanical property, accurate shape dimension, and stable quality because the railway body is composed with many different kinds of extruded profiles. Therefore, it is necessary to research about Aluminum precision-extrusion technology to maintain exit temperature and die load. The goal of this project is applying the Aluminum extrusion profile to next-generation railway car body by developing the Aluminum extrusion profile according to precision-extrusion technology which may maintain isothermal exit temperature.