• KSII Transactions on Internet and Information Systems (TIIS)
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• 제5권5호
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• pp.999-1012
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• 2011

This paper proposes an algorithm that enables mobile nodes to implement self-regulated movements in mobile ad-hoc networks (MANETs). It is important for mobile nodes to maintain a certain level of network-based stability by harmonizing these nodes' movements autonomously due to their limited transmission range and dynamic topology. Entropy methods based on relative position are suggested, as a means for mobile nodes to regulate their local movements. Simulations show that an early warning mechanism is suitable to maintain movement-based stability. Isolation can be reduced by 99%, with an increased network cost of 12% higher power consumption, using the proposed algorithm.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 통신소사이어티 추계학술대회논문집
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• pp.60-63
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• 2003

This paper describes the design and the simulation of a V-band single pole double throw (SPDT) FET switch fur millimeter-wave applications using drain impedance transformation network with CPW transmission line. The designed switch has about 10% bandwidth at 60GHz. Insertion loss is better than 3dB fur the ON state and Isolation is larger than 30dB fer the OFF state. The maximum isolation is 43.4dB at 60GHz with input power of 10dBm. The yield analysis is done considering the effects of pHEMT variations.

• 대한전자공학회논문지SD
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• 제44권4호
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• pp.32-42
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• 2007

[ $0.35{\mu}m$ ]twin-well non-epitaxial CMOS 공정에서의 substrate noise에 의한 아날로그 회로의 성능 저하를 예측하기 위하여 substrate 저항을 모델링하였다. Substrate 저항 모델 방정식은 P+ guard-ring isolation에 적용되어 측정값과 일치함을 확인하였다. Substrate 저항을 네 가지 형태로 구분하고 각각에 대하여 semi-empirical 모델 방정식을 확립하여, 측정값과 비교하여 rms 오차가 10% 미만이 되었다. 이 substrate 저항 모델을 guard-ring에 의한 isolation 구조에 적용하기 위하여 모델 방정식과 ADS(Advanced Design System) 회로 시뮬레이션에 의한 결과와 Network Analyzer의 측정 결과를 비교하였고, 비교적 잘 일치함을 확인하였다.

• 제어로봇시스템학회논문지
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• 제8권3호
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• pp.256-263
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• 2002

Optical Multistage Interconnection Networks(OMINs) comprising photonic switches have been studied extensively as important interconnecting building blocks for communication networks and parallel computing systems. A basic element of photonic switching networks is a 2$\times$2 directional coupler with two inputs and two outputs. This paper is concerned with the diagnosis of cross-talk-faults in OMINs. As the size of today's network becomes very large, the conventional diagnosis methods based on tests and simulation have become inefficient, or even more, impractical. In this paper, we propose a simple and easily implementable algorithm for detection and isolation of the single crosstalk-fault in OMINs. Specifically, we develope an algorithm fur the isolation of the source fault in switching elements whenever the single crosstalk-fault is detected in OMINS. The proposed algorithm is illustrated by an example of 16$\times$16 banyan network.

• 한국항행학회논문지
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• 제3권1호
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• pp.32-43
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• 1999

본 논문에서는 터보제트 엔진 제어기의 신뢰성을 향상시키기 위한 지능형 고장진단 알고리즘을 제안하였다. 제안된 기법은 다층 신경망을 이용한 고장진단 기법으로 서로 다른 종류의 센서를 사이의 기능적 종속관계를 추정하여 고장 부위를 규명하고 처치한다. 고장센서 신호는 역전파 알고리즘을 이용한 훈련된 신경망을 통하여 추정한다. 실험데이터에 기초한 터보제트 엔진의 선형공간 모델에 적용한 시뮬레이션을 통하여 제안된 알고리즘의 구현 가능성을 검증한다.

• 한국노년학
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• 제30권3호
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• pp.895-910
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• 2010

본 연구는 지역사회에 거주하고 있는 65세 이상 빈곤노인의 사회적 고립이 생활만족도에 어떠한 영향을 미치는지 살펴보고자 하였고, 사회적 고립이 생활만족도에 미치는 영향에서 사회적 인식이 매개효과를 가지는지를 검증하였다. 이를 위해 기장복지네트워크 조사연구(2009) 자료를 활용하였고, 이 자료중 부산시 기장군에 거주하고 있는 기초생활 수급대상자 또는 1,2종의 의료보호 대상자이면서 65세 이상 노인 256명의 자료를 분석대상으로 하였다. 자료 분석을 위해 상관관계 분석과 구조방정식에 의한 매개효과검증을 하였다. 연구결과에 의하면 조사대상노인의 5.5%는 극도의 사회적 고립을 경험하였고, 조사대상의 31%가 사회적 고립을 경험하고 있는 것으로 나타났다. 그리고 지역사회인식은 사회적 고립과 생활만족도와의 관계에서 매개효과를 가지는 것으로 나타났다. 이러한 연구결과들을 바탕으로 노인의 사회적 고립을 예방하기 위한 지역사회개입과 노인들의 사회참여 및 사회관계를 강조한 사회적고립 예방프로그램의 개발이 필요하다고 제안하였다.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2005년도 종합학술발표회 논문집 Vol.15 No.1
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• pp.231-234
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• 2005

In this paper, Dual-polarized Tx/Rx antenna for RFID reader is designed and fabricated to apply to RFID reader. Each feeding network of Tx/Rx is designed to improve the port-isolation and cross-polarization, and sequential rotation feeding scheme has been applied to increase of axial ratio bandwidth. Measured results show that 2.35dBi of antenna gain in 900MHz$\sim$928MHz, 150MHz of 3dB axial ratio bandwidth, -38dB$\sim$-40dB of port-isolation, and -30dB$\sim$-40dB of cross-polarization.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.174-176
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• 2007

Because of accident or leak of electricity, high voltage electricity can be conducted to vehicle chassis and damage human. Therefore the unit for detecting ground fault is necessary to minimize loss of life or equipment damage. Isolation resistance must be monitored for detecting ground fault. GFD(Ground Fault Detection) unit continually generate the pulse voltage between high voltage network and chassis. This will be sensing the returned current, calculate the isolation resistance and make decision the ground fault. This paper describes the method detecting ground fault.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1724-1725
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• 2007

This paper presents a fault detection and isolation(FDI) scheme for a nonlinear systems with a actuator and sensor faults. A residual generator based on the observer model generate the information for a fault detection. The proposed fault estimators are activated for a fault isolation and applied to estimate the time-varying lumped faults(model uncertainty + fault). but a fault estimator error dose not converge to zero since the derivative of lumped fault is not zero. Then the fuzzy neural network(FNN) is used to estimate the fault estimator error. Simulation results are presented to illustrate the effectiveness and the applicability of the approaches proposed.

• Earthquakes and Structures
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• 제3권3_4호
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• pp.315-340
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• 2012

There are many types of seismic isolation devices that are being used today for structural control of earthquake response in buildings. The most commonly used are sliding bearings and elastomeric bearings, the latter with or without lead core. An alternative solution is the use of steel springs combined with viscoelastic fluid dampers, which is the case discussed in this paper. An analytical study of a three-story building supported on helical steel springs and viscoelastic fluid dampers, GERB Control System (GCS), subjected to near-fault earthquakes is presented. Several earthquakes records have been obtained by the acceleration network installed in the isolated building and in its non-isolated twin since they were finished. These experimental results are analysed and discussed. The aim is to show that the spring-based system can be an alternative for base isolation of small building located near active faults.