• 대한기계학회논문집A
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• 제29권8호
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• pp.1093-1101
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• 2005

Hybrid mass damper systems have recently been introduced as a dynamic vibration absorber to exploit the benefits of both the conventional tuned mass damper system and the active control system. A hybrid system is programmed to function as either a conventional TMD or as an active system according to the wind conditions and the resultant building and damper mass vibration characteristics. This paper deals with the design of the robust controller for the control of the flexible box structure. The control algorithm was devised based on $H_2$(LQG) robust control logic with acceleration feedback and to improve the capability of the controller Kalman Filter was accepted for the system. To test the ability of the robust controller using the linear motor damper system, performance tests and simulations were carried out on the full-scale steel frame structure. Through the performance tests, it was confirmed that acceleration levels are reduced down.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.562-567
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• 2001

The number of required modes to provide accurate force information in a truncated model of a flexible structure is investigated. In the case of modal truncation of a distributed parameter system, the difference in convergence rates between displacements and forces is discussed. The residual flexibility, a term from past literature, is used to recapture some of the lost force information in a truncated model. This paper presents numerical and experimental results of a study where the residual flexibility is used in conjunction with a Kalman filter so that accurate force information may be obtained from a small set of displacement measurements with a reduced-order model. The motivation for this paper is to be able to obtain accurate information about unmeasurable dynamic reaction forces in a rotating machine for diagnostic and control purposes.

• 한국정밀공학회지
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• 제19권1호
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• pp.150-157
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• 2002

The number of required modes to provide accurate force information in a truncated model of a flexible structure is investigated. In the case of modal truncation of a distributed parameter system, the difference in convergence rates between displacements and forces is discussed. The residual flexibility. a term from past literature, is used to recapture some of the lost force information in a truncated model. This paper presents numerical and experimental results of a study where the residual flexibility is used in conjunction with a Kalman filter so that accurate force information may be obtained from a small set of displacement measurements wish a reduced-order model. The motivation for this paper is to be able to obtain accurate information about unmeasurable dynamic reaction forces in a rotating machine for diagnostic and control purposes.

• ETRI Journal
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• 제38권5호
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• pp.988-995
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• 2016

In this paper, we present a new specific and customized interface tool with parameter identification of Modified Butterworth-Van Dyke models for ladder bulk acoustic wave filters. The aforementioned tool is easy to use and flexible because it allows simulations and reengineering to be conducted in an application. A modular design approach is applied to simplify the extension of the proposed tool for different topologies. The proposed tool was validated using measurements from an aluminum-nitride based ladder BAW filter dedicated to the frequency ranges of the Universal Mobile Telecommunications Service and standards and Wideband Code Division Multiple Access.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2016년도 임시총회 및 하계학술연구발표회
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• pp.176-176
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• 2016

• 자원환경지질
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• 제20권2호
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• pp.119-123
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• 1987

0차의 Hankel 변환은 Abel 변환과 Fourier 변환의 결합으로 나타낼 수 있다. 이 Abel-Fourier법은 샘플링 간격이 일정하지 않는 중합필터를 사용한 신속한 Abel 변환과 고속 Fourier 변환으로 작성될 때, 종래의 디지탈 선형필터법보다 계산시간면에서 유리하다. 그러나, Abel-Fourier법은 일반적으로 잘 설계된 디지탈 필터보다 정확하지는 않다. 전기탐사 문제에 이들 방법을 적용할 때, 디지탈 필터법이 Abel-Fourier 법보다 더 융통성이 많은 것으로 생각된다.

• 한국전자파학회논문지
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• 제13권1호
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• pp.12-18
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• 2002

본 논문에서는 가변 감쇠극을 갖는 새로운 구조의 유전체 공진기 대역통과 여파기를 제안하였다. 새로운 구조의 여파기는 일반적인 유전체 공진기 여파기와 유사하지만 유전체 공진기 아래에 마이크로스트립 선로를 부가하여 감쇠극의 위치를 옮길 수 있을 뿐만 아니라 여파기의 차단 특성을 향상시킬 수 있다. 제안된 여파기를 이용한 듀플렉서는 일반적인 여파기를 이용한 것보다 우수한 격리도와 차단 특성을 나타냈고, 제작된 듀플렉서의 측정 결과는 모의실험 결과와 일치하였다.

• 대한전기학회논문지
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• 제45권1호
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• pp.123-130
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• 1996

Due to high payload capacity and high length-to -cross-section ratio requirements, long-reach manipulator systems are expected to exhibit significant structural flexibility. To avoid structural vibrations during operations, various types of input shaping filtering methods have been investigated. A robust notch filtering method and an impulse shaping filtering method were investigated and implemented. In addition, two very different approaches have been developed and compared. One new approach, referred to as a

• 통합자연과학논문집
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• 제6권4호
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• pp.244-250
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• 2013

Three types of functionalized flexible optical composite films based on Bragg structure porous silicon interferometer have been successfully fabricated by casting a toluene solution of polystyrene onto the free-standing porous silicon. The optical properties of composite films are measured. Surface functionalization of porous silicon is determined by FT-IR measurement. Reflectance and transparence properties of composite films are measured for the possible application of tunable optical filter and indicate that the transmission peak occurred at the identical location where the reflection peak appeared.

• 한국전자파학회논문지
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• 제19권3호
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• pp.343-351
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• 2008

본 논문에서는 FPC(Flexible Printed Circuit) 케이블에 적층된 나선형 인덕터를 내장하여 다기능 케이블을 위한 공통 모드 필터를 제안하였다. 공통 모드 필터가 내장된 FPC 케이블은 별도의 SMD(Surface Mounted Device) 필터 없이 연성 케이블과 공통 모드 차단 특성을 가짐으로서, 다기능 케이블이라는 새로운 개념을 제시한다. 내장된 공통 모드 필터는 광대역의 공통 모드 차단 대역을 가지고 손실이 큰 페라이트와 같은 자성 물질을 사용하지 않아 차동 모드 삽입 손실 및 반사 손실이 향상되었다. 3-turn 인덕터를 가진 공통 모드 필터는 공통 모드차단 대역이 $0.4{\sim}3.12GHz$이며, 페라이트를 적용한 상용 LTCC(Low Temperature Co-fire Ceramic) 공통 모드 필터에 비해 3 GHz에서 1.95 dB, 8 GHz에서 6.97 dB의 향상된 차동 모드 삽입 손실을 갖는다.