• Corrosion Science and Technology
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• v.8 no.1
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• pp.40-43
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• 2009

We investigated the corrosion resistance of Zn and Cu coated steel pipes as a substitute for Cu pipe in an air-conditioner system. In addition, the galvanic corrosion tendency between two dissimilar metal parts was studied. The corrosion resistance of the Cu electroplated steel was similar to that of Cu, while the corrosion rate of the Zn electro- galvanized and the galvalume (Zn-55 % Al) coated steels was much higher and not suitable for Cu substitute in artificial sea water and acidic rain environments. Furthermore, the galvanic difference between Cu electroplated steel and Cu was so small that the Cu coated steel pipe can be used as a substitute for Cu pipe in an air-conditioner system.

• 한국약용작물학회:학술대회논문집
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• 2007.05a
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• pp.76-77
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• 2007

• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.230-230
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• 2003

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.11
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• pp.493-497
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• 2005

This paper dealt with the influence of harmonic voltages on arrester diagnostics and its compensation method by using a designed Pspice arrester model. A pure sinusoidal voltage and its 3$^{rd}$ harmonic voltage were applied to the model, and the leakage current components were analyzed. The simulation results have shown that the peak value of resistive leakage current depends not only on the phase of the 3$^{rd}$ harmonic voltage but also on the magnitude of it. In this paper, an approximated 5$^{th}$ order polynomial formula by the Least-Square-Technique was derived, and correction factors which compensate the error caused by the 3$^{rd}$ harmonic voltage were calculated.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.346-348
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• 2005

무선 통신망은 유선 통신망에 비하여 대역이 한정적이기 때문에 효율적인 대역의 이용은 매우 중요하다. 그러나 802.16 BWA 시스템의 UGS 알고리즘은 보낼 데이터가 없어도 일정한 간격으로 고정 대역을 단말에 계속 할당하기 때문에 대역의 낭비가 심하다. 본 논문에서는 VAd가 가능한 단말에서 UGS 알고리즘을 이용할 때, 보낼 패킷이 없는 경우에는 그 유휴 대역을 이용하여 우선순위가 낮은 nrtPS나, BE 알고리즘을 이용하는 패킷을 대신 전송하는 방법을 제시함으로써, 802.16 BWA 시스템에서 효율적인 상향링크 스케줄링을 구현한다.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.37-39
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• 2005

컴퓨터통신기술과 정보처리기술의 발전으로 멀티미디어 콘텐츠의 활성화를 촉진하였다. 정보화시대 국가경쟁 사업으로 정부차원에서도 문화 콘텐츠 개발을 국제적 경쟁력을 가진 고품질의 문화콘텐츠를 제작공급할 수 있는 핵심 성장기반을 조성하기 위하여 국가사업으로 확대하고 있다. 본 논문에서는 멀티미디어 콘텐츠 보호를 위하여 해치체인 알고리즘을 이용한 멀티미디어 데이터의 암호화 기법을 제안하였으며, 인가된 사용자 확인을 위하여 사용자인증 및 키 전송 알고리즘을 이용하여 사용자인증 및 키전송 프로토콜을 설계하였으며, 복호화시 재생 지연시간을 줄이기 위하여 이중버퍼를 구성 효율적인 버퍼 스케줄을 이용하여 멀티미디어 콘텐츠의 실시간 복호화 방법을 제안한다.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.317-325
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• 2011

Vehicle model validation for the static vehicle testing has been done by comparison of the simulation results and test results and the parameters of the vehicle model to be used in the simulation have been adjusted to reflect the measured behaviour. The vehicle model fort the simulation should be validated by suitable tests and/or practical experience. The static vehicle test used to validate the vehicle model are the weight measurement, the wheel offloading test, the bogie rotational resistance test and the sway test. Finally, the computer simulation model has been validated and using the validated vehicle model the acceptance of the vehicle safety of the resistance to flange climbing derailment at low speed can be examined.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.3099-3103
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• 2011

In measurement of risk voltages; the step and touch voltage, the distance between the current electrode and the ground electrode recedes up to several hundred meters as the scale of grounding system increases. This paper dealt with the measurement method of risk voltage in a restricted space. The risk voltage was analyzed depending on the distance and the direction of the current electrode from the ground electrode in a $10[m]{\times}10[m]$ mesh grounding system. The average value of risk voltages measured at a point 20 [m] away from the current electrode was deviated below 5 [%] from that measured at 100 [m] point. Consequently, the evaluation of risk voltage of a large-scale grounding system buried in a spatially restricted place is available if the current electrode is installed in symmetry to the ground electrode.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2010.11a
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• pp.153-154
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• 2010

본 논문은 SC-FDE 기반 3D-HDTV 지상파 방송을 위한 MISO 구조의 SFN을 구성하고 STBC방식의 데이터 송신기업과 방송망 내 수신기의 위치에 따라 발생하는 두 개의 송신신호의 도달 시감의 차이를 극복하기 위한 채널추정기법을 제안한다. 모의실험을 통하여 브라질 채널에서 두 개의 송신신호의 차이에 따른 제안된 기법의 성능을 확인하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.213-215
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• 2012

The current Navigation System for the Visually Impaired Person has a short and limited communication distance and can't receive enough information from Visually Impaired Person to assist directly. In addition, because the path is dangerous and incomplete for the Visually Impaired Person, moving with White Stick is still inconvenient and dangerous. To solve this problem we implement communication that can send and receive video, voice, location information between the Visually Impaired Person's Android platform and assistant's PC.