• Title/Summary/Keyword: coupled

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A Study on Coupled Vibrations of Diesel Engine Propulsion Shafting (1st Report: Effects of Coupling on Natural Frequencies and their Modes) (디젤기관 추진축계의 연성진동에 관한 연구(제1보:연성이 고유진동수와 그의 모드에 미치는 영향))

  • 전효중;이돈출;김의간
    • Journal of Advanced Marine Engineering and Technology
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    • v.25 no.1
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    • pp.95-106
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    • 2001
  • When the crankshaft of diesel engine has more than 3 throws, which are arranged in a different plane, its vibration induces coupled motions, especially the coupled torsional and axial vibration. Nowadays, the torsional vibration which is influenced rather weak than axial one, can be theoretically calculated fairly accurately, but theoretical calculation results of the axial vibration which is influenced strongly from torsional vibration is not so good. To get accurate calculation results of axial vibration, coupled axial-torsional vibration must be treated. In this investigation, coupled effects of vibration of diesel engine propulsion shafting are analyzed theoretically and some simple calculation methods are also studied. On this first report, effects of coupling on natural frequencies and their modes are mainly studied, setting the each mass in 4 degrees of freedom.

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A Study on Whispering Gallery Mode Dielectric Coupled Resonator which Englarges the Free Spectral Tange (공진주파수 간격을 확장시키는 Whispering Gallery 모드 유전체 복합공진기에 관한 연구)

  • 황재효;민경일;구경완
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.11 no.7
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    • pp.1225-1232
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    • 2000
  • In this paper, a new coupled resonator which expands free spectral ranges (FSR) of the W. G. mode resonators is presented. The proposed coupled resonator consists of two dielectric disks. The resonance frequency of the coupled resonator is equivalent to the frequency, which satisfies the individual resonance conditions of each disk at the same time. As the results, the FSR is expanded. The coupled resonator proposed in this paper at K-Band is fabricated by using dielectric disks and the dielectric straight waveguides. The validity of proposed coupled resonator was verified through experiments.

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Analytical Study on the Free Vibration of Two Rectangular Plates Coupled with Fluid (유체로 연성된 두 직사각 평판의 고유진동에 관한 해석적 연구)

  • 유계형;정경훈;이성철
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.647-651
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    • 2002
  • This study dealt with the free vibration of two identical rectangular plates coupled with fluid. In order to investigate the vibration characteristics of fluid-coupled rectangular plates, an analytical method based on the finite Fourier series expansion and Rayleigh-Ritz method was suggested. A commercial computer code, ANSYS was used to perform finite element analysis and we investigated the vibration characteristics with mode shapes and natural frequencies. As a result, the transverse vibration modes, in-phase and out-of-phase, were observed alternately in the fluid-coupled system. The effect of fluid bounding and plate boundary condition on the fluid-coupled natural frequency were investigated. It was shown that the mode numbers increased, the normalized natural frequencies monotonically increased.

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Dynamic Analysis of Bending-Torsion Coupled Beam Structures Using Exact Dynamic Elements

  • Hong, Seong-Wook;Kang, Byung-Sik;Park, Joong-Youn
    • International Journal of Precision Engineering and Manufacturing
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    • v.4 no.1
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    • pp.15-22
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    • 2003
  • Beams are often subject to bending-torsion coupled vibration due to mass coupling and/or stiffness coupling. This paper proposes a dynamic analysis method using the exact dynamic element for bending-torsion coupled vibration of general plane beam structures with joints. The exact dynamic element matrix for a bending-torsion coupled beam is derived, and the detailed procedure of using the exact dynamic element matrix is also presented. Three examples are provided for validating and illustrating the proposed method. The numerical study proves the proposed method to be useful for dynamic analysis of bending-torsion coupled beam structures with joints.

Studies on Coupled Vibration of Diesel Engine Propulsion Shafting (디젤기관 추진축계의 연성진동에 관한 연구 (제1보:연성이 고유진동수와 그의 모드에 미치는 영향))

  • 김의간
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2000.05a
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    • pp.60-71
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    • 2000
  • When the crankshaft of Diesel engine has more than 3 throws which are arranged in a different plane its vibration induces coupled motions especially the coupled torsional and axial vibration. Nowadays the torsional vibration which is influenced rather weak than axial one can be theoretically calculated fairly accurately but theoretical calculation results of the axial vibration which is influenced strongly from torsional vibration is not so good. To get accurate calculation results of axial vibration coupled axial-torsional vibration must be treated. in this investigation coupled effects of vibration of Diesel engine propulsion shafting are analyzed theoretically and some more simple calculation methods are also studied. On this first report effects of coupling on natural frequencies and their modes are mainly studied setting the each mass in 4 degrees of freedom. later this problem may be studied again by setting each mass as 6 degrees of freedom.

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SCI Scheme for Hybrid 3G Networks (하이브리드 3G 네트워크를 위한 SCI 기술)

  • Kim, Gui-Jung;Kim, Seok-Hoon;Han, Jung-Soo
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.677-681
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    • 2009
  • The Smoothly Coupled Integration (SCI) proposed in this paper takes only the strength of loosely coupled integration and tightly coupled integration. Furthermore, 3G network and WiBro network, which are coupled with SCI, have independent architecture which supports mobility and seamless services by fast handoff. Computer simulation with the use of OPNET marked excellence in performance of smoothly coupled integration.

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Design of Dual-Band Pass Filter Using Parallel Coupled SIR (Parallel Coupled SIR을 이용한 이중대역 통과필터 설계 연구)

  • Kim, Koon-Tae;Paek, Hyun;Kim, Hyeong-Seok
    • 한국정보통신설비학회:학술대회논문집
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    • 2009.08a
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    • pp.215-218
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    • 2009
  • In this paper, Dual-band bandpass filter studied design using Parallel Coupled SIR(Stepped Impedance Resonator). This Dual-band bandpass filter design SIR of half-wavelength by Parallel-coupled type that is available to RFID system and Changed structure in Meander form by size reduce. Because seen Dual-band bandpass filter is designed so that is applicable for frequency 433MHz and 2.45GHz of RFID system is very wide distance between two pass-band, establish 433MHz by fundamental frequency and controlled 2.45GHz by 2st spurious resonance frequency bandstop filter of 1st spurious resonance frequency and Parallel coupled SIR Combine to remove 1st spurious resonance frequency.

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Design and Characteristics of AE Sensor for GIS by Finite Element Analys (유한요소해석을 이용한 GIS용 AE 센서의 설계와 특성)

  • Hong, Jae-Il;Lee, Byung-Hyo;Kim, Il-Nam;Cho, Tae-Kyung;Yoo, Ju-Hyun
    • Proceedings of the KIEE Conference
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    • 2000.07e
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    • pp.52-55
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    • 2000
  • In this paper, the coupled and the non-coupled vibration mode AE sensor for GIS were simulated by finite element analysis and manufactured, and characterized. The maximum sensitivity was 64.3 dB when the resonant frequency of the coupled vibration mode AE sensor was 166 kHz and the maximum sensitivity was 58.9 dB when the resonant frequency of the non-coupled mode AE sensor was 265 kHz. The coupled vibration mode AE sensor responded higher than the non-coupled vibration mode AE sensor at the partial discharge detection in GIS.

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Applicatio of Finite Element and Boundary Element Methods to Predict Steady-State Response of a Structure-Acoustic-Cavity System (구조-음향계의 정상상태 응답예측을 위한 유한요소법과 경계요소법의 응용)

  • Lee, Cang-Myung
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.5
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    • pp.1383-1391
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    • 1996
  • The steady-state response for a coupled structure-acoustic-cavity systme has been investigated by numerical technique using a directly coupled finite element method(FEM) and Boundary Element Method(BEM) model. The Laplace tranformed matrix equations for the structure and the acoustic cavity are coupled directly satisfying the necessary equilibrium and compatibility conditions. The coupled FEM-BEM code is verified by comparing its prediction for an example with known analytical, numerical and experimental results. The example involves a coupled structure-acoustic-cavity system which is a box-type cavity with one end as experimentally excited pinned-pinned plate.

Characteristics of Wave Transmission Through Various functions in Coupled Beams (연성보에서 연결 구조에 따른 파동 전달 특성)

  • 이병철;길현권;이효행;이용현;홍석윤
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.05a
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    • pp.468-473
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    • 2004
  • The objective of this paper is to analyze the characteristics of wave transmission through various junctions in coupled beams. The in-plane vibration as veil as the out-of-plane vibration are generated due to the wave conversion at the junctions in the coupled beams. The out-of-plane vibration is associated with propagation of out-of-plane waves (flexural waves). The in-plane vibration is associated with propagation of in-plane waves (longitudinal and torsional waves). In order to effectively reduce vibration and structure-borne noise, it is necessary to understand the characteristics of wave conversion at various junctions in the coupled structures. The numerical results in this paper have showed the characteristics of wave transmission through various junctions in coupled beams. Those could be helpful to designer to develop the idea to reduce vibration and structure-borne noise.

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