• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.110-112
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• 2009

Transient acoustic pressure in the near field of an impacted plate carries information that can be utilized for recovering the impact force history. The inverse calculation approach using BEM-based NAH, which is conventionally used for time harmonic excitation, can be applied for reconstructing the transient waves using the principle of Fourier transform and spectral analysis. Then, using the recovered velocity in normal direction of the plate surface, the corresponding structural intensity can be obtained and the identification of input power can be performed. However, several manipulations should be given to overcome numerical artifacts, such as aliasing and erratic oscillation at discontinuity, and to suppress the effect of noise. Experiment using a simply supported plate is presented for demonstration purpose.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.2
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• pp.263-269
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• 2012

In order to present that the electromagnetic compatibility standards following the frequency goes up which is based automotive electronics, in this paper, a hybrid/electric vehicle battery which reflects the frequency of the equivalent circuit model is introduced. By using this circuit modeling, the impedance characteristics can be analysed and an analyze of battery one cell is finished. Using this model, each different from the discharging situation, the discharge characteristic curve could be led. Basic theoretical approaches and measuring results through MATLAB and experimental validation of the EIS measurement equipment was used.

• Proceedings of the Korea Information Processing Society Conference
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• 2006.05a
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• pp.113-116
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• 2006

GPS 및 PDA 등의 발달과 보급으로 인해 위치기반서비스(LBS), 차량항법장치(CNS), 지리정보시스템(GIS)등 공간 데이터를 이용하는 응용프로그램이 급격하게 발달되었다. 응용프로그램의 발달과 더불어 이동객체의 양이 방대해짐에 따라 객체에 대한 효율적 처리가 요구된다. 이동 객체가 시간의 흐름에 따라 연속적으로 발생되는 위치 정보를 신속하게 관리하기 위한 통합된 인덱스 구조를 제안한다. 제안하는 인덱스구조는 이동 객체의 현재, 과거, 미래질의를 처리할 수 있도록 3 가지의 인덱스를 통합 하였으며, 또한 제안된 인덱스구조에 저장 관리자를 함께 둠으로써 이동 객체정보를 관리 할 수 있다.

• Imaging Science in Dentistry
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• v.33 no.4
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• pp.207-209
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• 2003

Purpose: To evaluate the clinical and radiographic features of unilateral hyperplastic mandibular condyles for some useful preliminary diagnostic recommendations. Materials and Methods : Clinical records, radiographs and histologic diagnoses of 35 cases with asymmetric mandibular condyles due to apparent unilateral condylar hyperplasia were evaluated retrospectively. Results: Among 35 cases, 28 were true hyperplastic conditions of condyles whereas the remaining 7 were unilateral internal derangement occurring on the short side. 17 of the 28 hyperplastic condyles showed a mass or irregular radiographic shadow with histologic diagnosis including osteochondroma and osteoma. Only 5 of these cases showed facial asymmetry. 2 out of the 17 cases showed hyperplastic round shaped irregular condyles consistent with ankylosis and their histologic diagnoses were osteochondromas. 11 of the 28 cases showed smooth enlargement of condylar head with elongation of the neck causing facial asymmetry, but histologic diagnoses were not available because the surgical operation conserved the condyles. Conclusion: The hyperplastic conditions of the mandibular condyles include not only true hyperplasia, osteochondroma, osteoma, and ankylosis, but also unilateral internal derangement occurring on the short side.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.258-259
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• 2011

This paper shows the load characteristics of IH (Induction Heating) Cookers which are those of essential appliances for electrifying residential buildings in smart places. Load experiments are carried out in the same manner as like previous two studies. The results will be used to develop new load models for smart places including heat pump loads for analyzing changed power system environments by the smart grid.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1652-1653
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• 2011

This paper builds a printed circuit board to calculate the radiated emissions due to the common-mode and differential-mode currents. The calculated results agree with the measured values. Based on the calculated values, it is shown clearly that the common-mode radiations are the dominator of the radiated emissions from the device. The radiated emissions due to the common-mode currents can easily dominate the radiated emissions from the printed circuit board.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.208-211
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• 2004

In order to obtain improved concrete mix proportion on nuclear power plant structures, the properties of normal concrete is compared with self-compacting concrete. In addition, various mixes of self-compacting concrete utilizing melaminic acid based admixture is mutually compared and estimated. Because existing normal concrete mixes might occur high temperature in concrete structure, A new multi-component concrete, which declines hydration heat, is demanded. Therefore, in this study, the possibility of manufacturing self-compacting concrete is verified and what influences melaminic acid and various powders have on the properties of self-compacting concrete are investigated.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.10b
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• pp.855-858
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• 2001

통신 및 컴퓨터의 보급 발전을 통해 새로운 정보 사회의 패러다임이 정립되고 있다. 특히 유 무선 네트워크 상에서 그름 기반 통신 응용 서비스의 요구 증가는 더욱 빠르고 정확한 정보 통신의 한 축으로서 매우 중요한 의미를 부여받고 있다. 이러한 필요성에 따라 멀티캐스트 기반 구조에 대한 연구가 활발히 진행되고 있다. 그러나 유 무선 멀티캐스트 키 관리 구조에 대한 안전성과 효율성 및 확장성 부분에 대한 해결책은 아직 미비한 상태이다. 본 연구에서는 유선 및 무선에서 멀티캐스트 서비스 지원을 위해 필요한 요구 사항들을 고찰함과 동시에 안전성과 효율성 및 확장성을 제공하는 새로운 멀티캐스트 키 관리 기법을 제안한다.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.545-547
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• 2005

345kV youngheung tansmission line which has been constructed in the western sea is the first and the largest marine project in the world crossing the youngheung island and the sihwa bay. It helps the stabilization of power supply greatly to cope with the rapid growth of the electric power consumption in the metropolitan areas and Gyeonggi province. Haying constructed the project successfully with the purely domestic-developed technologies, KEPCO is able to not only accumulate more advanced technologies of the marine project but also establish a bridgehead toward overseas market. It is very meaningful that we completed project successfully in spite of many difficulties including the uncertainty of the first project in the sea and strong objections from the environment groups and local residents. In this paper I will briefly introduce the project, newly developed technologies and materials.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.05b
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• pp.1353-1356
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• 2003

본 논문에서는 EP 보안(IPsec : IP Security)이 적용된 보안 패킷들을 네트워크 상에서 실시간으로 수집하여 분석해 주는 IP 보안 패킷 분석기를 설계 및 구현하였다. 본 패킷 분석기는 TCP UDP IP, ICMP 등의 일반 네트워크 패킷과 키 교환을 위한 IKE 패킷, 보안 통신을 위한 AM, ESP 패킷 등을 실시간으로 수집하고 분석하는 기능을 갖는다. 본 패킷 분석기는 현재의 IPv4 패킷 뿐 아니라 차세대 인터넷인 IPv6 패킷에 대하여도 실시간 수집 및 분석 기능을 제공한다. 또한 본 분석기는 IPsec 엔진에 대한 보안성을 평가하기 위한 자동화된 평가기능도 제공해 준다. 개발한 패킷 분석기를 이용하여 ETRI에서 개발한 통합 IPsec 엔진에 대한 보안성을 평가한 결과도 함께 보인다.