• 제목/요약/키워드: Coupling coefficients

검색결과 180건 처리시간 0.026초

회절격자구조를 갖는 도파로 소자의 엄밀한 광선광학적 결합계수 계산 (Ray-optical determination of the coupling coefficients of waveguide gratings by use of the rigorous coupled wave theory)

  • 박선택;송석호;오차환;김필수
    • 한국광학회지
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    • 제10권4호
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    • pp.348-353
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    • 1999
  • 엄밀한 결합파를 적용하는 광선광학적 방법에 의해, 임의의 격자구조를 갖는 도파로 회절소자의 결합계수를 계산하였다. 엄밀한 광선광학적 방법으로 다양한 격자구조(사각형, 정현파, 삼각형, 사다리꼴)에 대한 결합계수를 계산하였으며, 기존의 근사적 광선광학적 방법이나 결합모드 방법들과 비교 분석하였다. 특히, 사각형 격자의 경우에는 격자의 깊이 변화뿐만 아니라 격자영역비(duty-cycle)에 따른 결합계수를 구하였다. 엄밀한 광선광학적 방법은 강한 결합조건에서도 기존의 방법들에 비하여 도파로 회절격자의 결합계수를 매우 정확하게 결정할 수 있음을 확인하였다.

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박막에서의 박막두께에 따른 자기탄성계수의 거동 예측 (Magnetoelastic Coupling Coefficients with Film Thicknesses in Ultrathin Films)

  • 송오성
    • 한국자기학회지
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    • 제5권2호
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    • pp.112-114
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    • 1995
  • 매우 얇은 박막에서 자기탄성계수는 효과이방성에너지와 마찬가지로 박막두께에 반비례하여, B/sup eff/ = B/sup b/ + B/sup s/ /t 으로 수학적, 물리적으로 예측됨을 보였다. 이러한 박막두께가 얇아질수록 표면자기탄성계수(surface magnetoelastic coupling coefficient)에 의한 영향이 커지므로 많은 공학적 의미를 내포하고 있다.

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연성평판에서의 파워투과 및 반사 특성 실험 해석 (Experimental Analysis of Power Transmission and Reflection In a Coupled Plate)

  • 이용현;길현권;이효행;이규형;홍석윤
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계 학술대회논문집(수송기계편)
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    • pp.170-173
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    • 2005
  • The objective of this paper is to perform measurements of power transmission and reflection coefficients in a coupled plate. The coupled plate has been divided into 2 subsystems. The out-of-plane vibration has been only considered with assumption of relatively small in-plane vibration. The coupling loss factors have been measured with consideration of the power balance condition. The power transmission and reflection coefficients has been estimated from the measured values of the coupling loss factors. The measured power transmission and reflection coefficients have been compared with the corresponding theoretical coefficients in a semi-infinite coupled plate.

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Cu/Ni/Cu 단결정 박막에서의 자기 탄성 계수 (The Magnetoelastic Coupling Coefficients in Cu/Ni/Cu thin Films)

  • 송오성
    • 한국자기학회지
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    • 제5권2호
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    • pp.109-111
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    • 1995
  • 단결정 Cu/ Ni/ Cu 박막의 자기탄성계수(magnetoelastic coupling coefficients)를 자성박막의 두께에 따른 효과이방성에너지(effective anisotropy energy)를 측정하여 현 상학적인 이론 모델로 구하는 방법을 제안하였다. 이러한 간접적인 방법으로 자기탄성 계수를 결정하는 방법은 다른 결정정계에서도 가능하다.

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복소 매칭을 이용한 Open Loop Resonator 다이플렉서 (Open loop resonator diplexer applying conjugate matching)

  • 백현;한형석;김형석
    • 한국정보통신설비학회:학술대회논문집
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    • 한국정보통신설비학회 2008년도 정보통신설비 학술대회
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    • pp.425-428
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    • 2008
  • A new type of cross-coupled planar microwave filter using coupled microstrip square open-loop resonators diplexer pro-posed. A method for the rigorous calculation of the coupling coefficients of basic four pole electric and magnetic coupling structures encountered. Simple empirical models are derived for estimation of the coupling coefficients. Experiments are performed to verify the theory. And a method for diplexer matching is conjugate matching that has characteristic better than open matching method.

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Alternative Expressions for Mutual Inductance and Coupling Coefficient Applied in Wireless Power Transfer

  • Kim, Gunyoung;Lee, Bomson
    • Journal of electromagnetic engineering and science
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    • 제16권2호
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    • pp.112-118
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    • 2016
  • Alternative analytic expressions for the mutual inductance ($L_m$) and coupling coefficient (k) between circular loops are presented using more familiar and convenient expressions that represent the property of reciprocity clearly. In particular, the coupling coefficients are expressed in terms of structural dimensions normalized to a geometric mean of radii of two loops. Based on the presented expressions, various aspects of the mutual inductances and coupling coefficients, including the regions of positive, zero, and negative value, are examined with respect to their impacts on the efficiency of wireless power transmission.

Models and Experiments for the Main Topologies of MRC-WPT Systems

  • Yang, Mingbo;Wang, Peng;Guan, Yanzhi;Yang, Zhenfeng
    • Journal of Power Electronics
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    • 제17권6호
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    • pp.1694-1706
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    • 2017
  • Models and experiments for magnetic resonance coupling wireless power transmission (MRC-WPT) topologies such as the chain topology and branch topology are studied in this paper. Coupling mode theory based energy resonance models are built for the two topologies. Complete energy resonance models including input items, loss coefficients, and coupling coefficients are built for the two topologies. The storage and the oscillation model of the resonant energy are built in the time domain. The effect of the excitation item, loss item, and coupling coefficients on MRC systems are provided in detail. By solving the energy oscillation time domain model, distance enhancing models are established for the chain topology, and energy relocating models are established for the branch topology. Under the assumption that there are no couplings between every other coil or between loads, the maximum transmission capacity conditions are found for the chain topology, and energy distribution models are established for the branch topology. A MRC-WPT experiment was carried out for the verification of the above model. The maximum transmission distance enhancement condition for the chain topology, and the energy allocation model for the branch topology were verified by experiments.

A HOPF BIFURCATION IN AN ATTRACTION-ATTRACTION CHEMOTAXIS SYSTEM WITH GLOBAL COUPLING

  • YoonMee Ham
    • Korean Journal of Mathematics
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    • 제31권2호
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    • pp.203-216
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    • 2023
  • We consider a bistable attraction-attraction chemotaxis system with global coupling term. The study in this paper asserts that conditions for chemotactic coefficients for attraction and attraction and the global coupling constant to show existence of stationary solutions and Hopf bifurcation in the interfacial problem as the bifurcation parameters vary are obtained analytically.

The characteristic analysis of contact-less Power supply by 3D finite element method

  • Park, Han-Seok;Cho, Yun-Hyun;Jung, Hong-Sub;Woo, Kyung-il;Kim, Kyung-Ho
    • Journal of Advanced Marine Engineering and Technology
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    • 제28권1호
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    • pp.145-151
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    • 2004
  • This paper proposes the calculation method of magnetic coupling coefficient of contact-less power supply by the 3D finite element method with a variation of the secondary core position. The primary, secondary self and leakage inductances and the capacitances of a resonant circuit are calculated by the finite element analysis results. The magnetic coupling coefficients are obtained also. The power factors are obtained by simulation for the magnetic coupling coefficients and compared.

Motion Analysis of Two Floating Platforms with Mooring and Hawser Lines in Tandem Moored Operation by Combined Matrix Method and Separated Matrix Method

  • KOO BON-JUN;KIM MOO-HYUN
    • 한국해양공학회지
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    • 제19권5호
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    • pp.1-15
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    • 2005
  • The motion behaviors including hydrodynamic interaction and mechanical coupling effects on multiple-body floating platforms are simulated by using a time domain hull/mooring/riser coupled dynamics analysis program. The objective of this study is to evaluate off-diagonal hydrodynamic interaction effects and mechanical coupling effects on tandem moored FPSO and shuttle taker motions. In the multiple-body floating platforms interaction, hydrodynamic coupling effects with waves and mechanical coupling effects through the connectors should be considered. Thus, in this study, the multiple-body platform motions are calculated by Combined Matrix Method (CMM) as well as Separated Matrix Method (SMM). The advantage of the combined matrix method is that it can include all the 6Nx6N full hydrodynamic and mechanical interaction effects among N bodies. Whereas, due to the larger matrix size, the calculation time of Combined Matrix Method (CMM) is longer than the Separated Matrix Method (SMM). On the other hand, Separated Matrix Method (SMM) cannot include the off-diagonal 6x6 hydrodynamic interaction coefficients although it can fully include mechanical interactions among N bodies. To evaluate hydrodynamic interaction and mechanical coupling effects, tandem moored FPSO and shuttle tanker is simulated by Combined Matrix Method (CMM) and Separated Matrix Method (SMM). The calculation results give a good agreement between Combined Matrix Method (CMM) and Separated Matrix Method (SMM). The results show that the Separated Matrix Method (SMM) is more efficient for tandem moored FPSO and shuttle tanker. In the numerical calculation, the hydrodynamic coefficients are calculated from a 3D diffraction/radiation panel program WAMIT, and wind and current forces are generated by using the respective coefficients given in the OCIMF data sheet.