• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.8 s.239
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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.

• Proceedings of the KSME Conference
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• 2001.11a
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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.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.1
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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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• v.38 no.5
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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.

• Proceedings of the Korean Magnestics Society Conference
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• 2016.05a
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• pp.176-176
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• 2016

• Economic and Environmental Geology
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• v.20 no.2
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• pp.119-123
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• 1987

Hankel transform of order 0 can be represented by a combination of Abel transform and Fourier transform. This Abel-Fourier method can offer computational advantages over a conventional digital linear filter method through the uses of a rapid Abel transform with shift variant recursive filter and of a fast Fourier transform. The Abel-Fourier method, however, is generally less accurate than a well-designed digital linear filter method. In geoelectrical applications, the digital linear filter method seems to be more flexible than the Abel-Fourier method.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.1
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• pp.12-18
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• 2002

In this paper a novel dielectric resonator (DR) bandpass filter (BPF) with flexible arrangement of attenuation poles is proposed. This DR filter is similar to a conventional DR filter except adding a microstrip line below a DR, which not only shifts the location of attenuation poles, but also improves skirt characteristics. The duplexer with the proposed DR BPF has been yielded better isolation and sharper skirt behavior than that with a conventional DR filter. The implemented duplexer has shown a good performance and been well agreed with the simulation.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.1
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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

• Journal of Integrative Natural Science
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• v.6 no.4
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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.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.3
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• pp.343-351
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• 2008

In this paper, a spiral shaped common mode filter(CMF) embedded in a flexible printed circuit board(FPCB) is proposed for a multi-function cable. The CMF embedded in a FPC cable presents a new concept as a multi-function cable by the common mode rejection characteristics without a surface mounted device(SMD) CMF. The embedded CMF has a wideband common mode rejection bandwidth and an enhanced differential mode characteristics compared to conventional CMFs that use a magnetic material such as a ferrite of high loss. The proposed CMF of 3 turn inductors has a common mode rejection bandwidth from 0.4 GHz to 3.12 GHz and has 1.95 dB at 3 GHz, 6.97 dB at 8 GHz improvements of a differential mode insertion loss compared to the commercial LTCC(Low Temperature Co-fire Ceramics) CMFs.