• Transactions of the Korean hydrogen and new energy society
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• v.25 no.1
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• pp.28-38
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• 2014

The organic-inorganic composite membrane in polymer exchange membrane fuel cells (PEMFCs) have several fascinating technological advantages such as a proton conductivity, thermal stability and mechanical properties. As the inorganic filler, silicon carbide (SiC) fiber have been used in various fields due to its unique properties such as thermal stability, conductivity, and tensile strength. In this study, composite membrane was successfully fabricated by modified-silicon carbide fiber. Modified process, as a novel process in SiC, takes reaction by phosphoric acid after oxidation process (generated homogeniusly $SiO_2$ layer on SiC fiber). The mechanical property which was conducted by tensile test of the 5wt% modified-$SiO_2@SiCf$ composite membrane was better than that of Aquivion casting membrane as well as ion cxchange capacity(IEC) and proton conductivity. In addition, the single cell performance was observed that the 5wt% modified-$SiO_2@SiCf$ composite membrane was approximately $0.2A/cm^2$ higher than that of a Aquivion casting electrolyte membrane and electrochemical impedance was improved with the charge transfer resistance and membrane resistance.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.497-499
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• 2002

This paper proposes the effective compensation method fur the IR lamp deterioration in NDIR capnograph system. The newly designed optical chamber with two IR lamps and an electronic hardware for controlling lamp intensity have been implemented. After applying the proposed optical chamber and reference lamp control circuit to the NDIR type capnograph system, it is identified that the proposed method can compensate the lamp deterioration effectively.

• Textile Coloration and Finishing
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• v.6 no.4
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• pp.1-8
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• 1994

To improve the antimicrobial activity and crease resistance of Korean traditional Hansan ramie fabrics, partially saponified polyethylene(PPS) was used as a softening water repellent agent and 3-(trimethoxysilyl)propyl dimethyl octadecyl ammonium chloride(QAC) as a antimicrobial agent. The antimicrobial activity was effective by treatments of PPS, QAC and PPS/QAC for shake flask test. For the halo test, PPS/QAC showed good antimicrobial activity. It was found that the desirable composition of H$_{2}$O/PPS/QAC is 98/1/1 for improving the antimicrobial activity and crease resistance of the fabrics.

• Journal of Mechanical Science and Technology
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• v.17 no.11
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• pp.1682-1692
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• 2003

This paper proposes an adaptive controller for partially known system and applies to a two-wheeled Welding Mobile Robot (WMR) to track a reference welding path at a constant velocity of the welding point. To design the tracking controller, the errors from WMR to steel wall is defined, and the controller is designed to drive the errors to zero as fast as desired. Additionally, a scheme of error measurement is implemented on the WMR to meet the need of the controller. In this paper, the system moments of inertia are considered to be partially unknown parameters which are estimated using update laws in adaptive control scheme. The simulations and experiments on a welding mobile robot show the effectiveness of the proposed controller.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.725-725
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• 2006

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.07a
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• pp.200-200
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• 2004

• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.554-557
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• 1999

This paper represent about design of the controller for battery of Guide-Eye Sign Lamp with traffic auxiliary system for power supply using solar cell. Simulation is represents V-I and power characteristic by Mathematical & Design Center 6.3 & Qnet 2.1. This system is successfully operating with high clearness lights.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1470-1473
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• 2005

We proposed new triode-type Field Emitter Arays using Carbon NanoTubes(CNT-FEAs) as electron emission sources at low electric fields. The CNTs were selectively grown on the patterned catalyst layer by Plasma-Enhanced Chemical Vapor Deposition (PECVD). In this structure, gate electrodes are located underneath the cathode electrodes and extracted gate is surrounded by CNT emitters. Furthermore, in order to control density of CNTs, we investigated effect of using rapid thermal annealing (RTA).

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.593-594
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• 2006

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1874-1877
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• 2002

The ramp waveform has recently been introduced to erase wall charges for AC PDP. However, it is difficult to erase completely the wall charges in all cases In this paper, new erase waveform having adaptive erasing characteristics are investigated. The erase margin of suggested waveform is wider than that of the conventional waveform. Moreover, suggested waveform can reduce the erase time significantly.