• 전력전자학회논문지
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• 제23권4호
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• pp.286-289
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• 2018

This paper tests the feasibility of using the transparent electrode as the electrode of the capacitor in order to use the vehicle glass of the electric vehicle for a capacitive coupling wireless transfer (CCWPT). Large coupling capacitance can be obtained due to large area and high permittivity using the glasses of an electric vehicle. However, if an electrode is formed on a metal such as copper, then a view cannot be guaranteed and a transparent electrode can pose a solution. Therefore, the coupling capacitor is implemented by forming a glass dielectric with an ITO transparent electrode on one side through a semiconductor deposition process. The loss of the coupling capacitor is investigated, and a 200 W CCWPT prototype is fabricated and tested for its characteristics and power transfer.

• 한국전자파학회지:전자파기술
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• 제2권4호
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• pp.47-54
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• 1991

본 논문에서는 전자파 해석에 관련된 기존의 해석 기법들을 간략하게 비교, 검토하고 GTD / UTD를 기본으로하여 고주파 해석 기법에 관련된 몇가지 문제들을 다룬다. 전자파 해석이란 전자파의 복사(radiation), 산란(scattering) 및 결합(coupling)에 관련된 문제의 해석을의미 한다. 전자파 해석은 여러 목적을위해 응용되고 있으며 EMC / EMI문제의 분석 및 대책 수립에도 응용될 수 있다. EMC / EMI 문제의 근원은 전자파의 간섭(interference) 현상이다. Emitting source로부터 복사(radiation)되는 간섭파는 여러 경로를 통해서 receptor로 coupling된다. 일반적으로 emitter와 receptor사이에는 여러 복잡한 구조물이 산란체로 작용하고 있으므로, emitter와 receptor사이의 직접경로(direct path)를 통한 coupling과 함께 구조물에 의한 전자파의 반사 및 회절을 통한 간접경로(indirect path)의 coupling도 고려되어야 한다. 따라서 EMC / EMI문제는 자유공간(free space)상에 있는 antenna 사이의 송수신 문제보다 매우 복잡하고 정확한 couplin의 계 산에 적지않은 어려움이 있다. EMC / EMI대책수립은 일차적으로 coupling path의 차단을 통해서 가능하므로 전자 파의 coupling path의 분석과 전자파의 복사 및 산란 mechanism에 대한 해석이 필수적이다.

• 대한기계학회논문집A
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• 제23권7호
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• pp.1085-1093
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• 1999

Thickness effects of coupling agent on residual bending stress were investigated in $Polyimide/SiO_2$ joints during thermal cycling. Thickness and peel strength of $\gamma$-APS coupling agent were measured and correlated with solution concentration and residual bending stress. The variation of residual bending stress with temperature was also measured for various thicknesses of the coupling agent. Finite element results were compared with experimental data for residual bending stress in $Polyimide/SiO_2$ joints.

• 한국소음진동공학회논문집
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• 제16권9호
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• pp.912-918
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• 2006

A modeling method for the vibration analysis of rotating multi-blade systems considering the coupling stiffness effect is presented in this paper. Blades are assumed as cantilever beams and the coupling stiffness effect originates from disc or shroud between blades. As the angular speed, hub radius ratio, and the coupling stiffness vary, the natural frequencies of the system vary. Numerical results show that the coupling stiffness is very important to estimate the natural frequencies. Along with the natural frequencies, associated mode shapes, critical angular speed, and critical hub radius ratio are obtained through the analysis.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제48권6호
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• pp.309-315
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• 1999

Coupling loss is generated by the time-varying external magnetic field in the normal matrix of the multi-filamentary HTS tape. This paper calculates the coupling loss in the HTS tape. Analytic calculation of the coupling loss cannot consider the effect of the different shapes and the arrangement of the filaments. Numerical calculation by using finite element method and analytic calculation of the coupling loss have been done in this paper and results of two calculations have been compared. Transverse magnetic field and longitudinal magnetic field were considered as the external field.

• Coupled systems mechanics
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• 제1권1호
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• pp.19-37
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• 2012

In this work, the iterative coupling of finite element and boundary element methods for the investigation of coupled fluid-fluid, solid-solid and fluid-solid wave propagation models is reviewed. In order to perform the coupling of the two numerical methods, a successive renewal of the variables on the common interface between the two sub-domains is performed through an iterative procedure until convergence is achieved. In the case of local nonlinearities within the finite element sub-domain, it is straightforward to perform the iterative coupling together with the iterations needed to solve the nonlinear system. In particular, a more efficient and stable performance of the coupling procedure is achieved by a special formulation that allows to use different time steps in each sub-domain. Optimized relaxation parameters are also considered in the analyses, in order to speed up and/or to ensure the convergence of the iterative process.

• Structural Engineering and Mechanics
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• 제27권2호
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• pp.149-172
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• 2007

An experimental study of five full-scale coupling beam specimens has been conducted to investigate the seismic behavior of strengthened RC coupling beams by bolted side steel plates using a reversed cyclic loading procedure. The strengthened coupling beams are fabricated with different plate thicknesses and shear connector arrangements to study their respective effects on load-carrying capacity, strength retention, stiffness degradation, deformation capacity, and energy dissipation ability. The study revealed that putting shear connectors along the span of coupling beams produces no significant improvement to the structural performance of the strengthened beams. Translational and rotational partial interactions of the shear connectors that would weaken the load-carrying capacity of the steel plates were observed and measured. The hierarchy of failure of concrete, steel plates, and shear connectors was identified. Furthermore, detailed effects of plate buckling and various arrangements of shear connectors on the post-peak behavior of the strengthened beams are discussed.

• 전력전자학회논문지
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• 제27권2호
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• pp.157-164
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• 2022

This study proposes an enhanced quadruple-Active-Bridge (QAB) converter that can solve power coupling problems. By adopting a multiple winding transformer, the equivalent circuit of a conventional QAB converter has power couplings between arbitrary output ports. This coupling is an unintended power relationship that complicates the regulation of output voltage of the multiple ports. The proposed converter can carry out power decoupling by changing the arrangement of the coupling inductor. Power transfer equations for the proposed converter and its operating principles are analyzed in detail. The power coupling caused by the transformer's leakage inductance is verified by using a proposed coupling factor that presents the relationship between inductance ratio and coupling power. In addition, the decoupling power control performance of the proposed converter is verified by simulation and a 3 kW prototype converter.

• 한국구조물진단유지관리공학회 논문집
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• 제21권2호
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• pp.95-102
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• 2017

본 연구는 철근상세(대각선 및 수평 철근상세)가 실규모 연결보의 구조성능에 미치는 영향을 평가하기 위하여 실시되었다. 연결보의 시공성 및 경제성을 향상시키기 위하여 고강도 철근(SD500 및 SD600)을 사용하였다. 반복하중이 작용하는 동안 연결보의 순경간(양쪽 전 단벽 사이의 간격)을 유지하기 위하여 강체 프레임 및 링크조인트를 설치하였다. 실험결과 대각선 철근상세을 적용한 연결보가 수평 철근상세 연결보에 비해 높은 연성을 나타내었다. AC1318-14 기준은 대각선 철근상세의 연결보 설계에는 적용이 가능할 것으로 판단되나, 수평 철근상세 연결보의 최대내력은 과대평가하는 것으로 나타났다. ASCE 41-13에서 제시된 연결보의 유효강성은 대각선 및 수평 철근상세를 적용한 연결보의 실험결과를 과대평가하고 있는 것으로 판단된다.

• 한국정보과학회논문지:소프트웨어및응용
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• 제36권11호
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• pp.891-900
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• 2009

소프트웨어의 수명이 길어짐에 따라, 소프트웨어 유지보수비용을 줄이기 위한 기법에 대한 연구의 중요도가 높아지고 있다. 소프트웨어 엔티티들간의 커플링(Coupling)정보는 소스코드 분석 및 리팩토링등의 소프트웨어 유지보수에 활동에서 의사결정시 정량적인 근거자료로 유용하게 사용되고 있다. 논리적 커플링(Logical Coupling)은 소프트웨어가 진화하는 과정에서 관측된 엔티티들간의 관계성 정도를 나타낸다. 논리적커플링이 처음 소개된 이후로, 커플링의 단위를 상세화 하는 연구가 발표됨으로써, 큰 단위의 엔티티간 논리적커플링으로는 설명할 수 없는 소프트웨어의 특성들이 설명되었다. 하지만, 기존 연구는 프로젝트 구성원들의 성향 및 프로젝트의 특성을 고려하지 못 하였다. 본 연구는 버전관리시스템의 변경기록에 담겨있는 프로젝트 구성원들의 성향과 프로젝트 자체의 특징을 고려한 다중관점 기반의 논리적커플링 측정기법을 제안하고, 오픈소스프로젝트를 통해 제안하는 기법을 검증하였다.