• 콘크리트학회논문집
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• 제17권6호
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• pp.1001-1009
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• 2005

고층 건물의 구조계획에서 벽체의 유용성은 오래전부터 인식되어 왔다. 구조물에서 적절한 위치에 벽체를 배치하며, 벽체는 구조물에 작용하는 횡하중에 매우 효과적으로 저항할 수 있다. 특히 병렬 전단벽 시스템의 구조물의 횡력저항 시스템으로서 가장 선호되는 구조이고 이러한 구조는 커플링보에 의해 벽체가 연결되게 된다. 커플링보는 강도, 강성, 연성 및 에너지 소산능력이 충분한 부재이어야 한다. 이러한 요구들을 만족시키기 위해 FBP를 적용한 철골 커플링보를 제안한다. FBP의 적용 여부를 변수로 하여 총 2개의 시험체를 계획하고 실험을 실시하였다. 이러한 실험 연구를 통하여 FBP를 적용한 철골 커플링보의 장점에 대해 서술하였고, 파괴모드를 제안하였다.

• 한국산학기술학회논문지
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• 제17권10호
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• pp.743-750
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• 2016

본 연구에서는 초고층건물의 횡력저항 구조형식으로 널리 사용되는 병렬전단벽-커플링보 구조시스템에서 전단벽의 강도, 강성이 커플링보의 설계 강도에 미치는 영향을 분석하였다. 커플링보에 발생하는 설계내력은 코어벽체의 두께와 콘크리트의 강도가 변하더라도 층별 설계내력은 유사한 경향을 보이고 있으며, 벽체 콘크리트 강도와 두께에 따라 커플링보에 발생하는 외력은 다소 감소하는 경향이 있다. 커플링보의 설계내력은 6개 모델 전부 40층 건물에서, 10층에서 15층의 범위에서 가장 높게 발생하고 있음을 알 수 있다. 즉, 병렬전단벽의 휨변형 변곡점이 형성되는 건물높이의 0.25H~0.375H 위치에서 최대 부재력이 발생한다. 벽체두께가 증가 할수록 코어내부의 커플링보의 발생 외력은 점차 증가하는 것으로 확인되었다. 또한 벽체 두께가 두꺼워질수록 벽체의 콘크리트 강도 증가에 따른 커플링보의 부재력 변화는 적게 나타나는데, 이는 벽체 두께가 두꺼우므로 콘크리트 강도변화의 영향이 적게 미치는 것으로 분석된다. 병렬전단벽의 두께증가는 콘크리트의 강도증가보다 강성변화에 큰 영향을 미치고, 이에 따라 커플링보의 부재력 변화에도 더 큰 영향을 미치는 것으로 분석된다.

• 한국광학회지
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• 제11권3호
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• pp.179-186
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• 2000

초고속정보통신망을 구성하는 교환기(ATM system)과 전송부문(B-NT(Broadband Network Termination) system, 10G 전송system 등)에 사용할 수 있는 155Mbps 수동 광정렬 방식의 광수신 모듈의 광결합 효율과 정렬오차 허용도를 게산하고 이를 적용한 엔지니어링 샘플로부터 이론치 비교와 flat-광섬유를 이용한 butt 커플링 패키지 방법으로 최대 -4.5dBm 광출력을 갖는 광송신기 제작 및 신뢰성 검사로 값싼 광송신기 제작에 대하여 알아보았다.

• 대한기계학회논문집A
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• 제20권7호
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• pp.2108-2117
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• 1996

The purpose of this paper is to investigate the influence of the exciter attached for the measurement of natural frequencies when extracting the frequency response functions of the test structure in experimental modal analysis. The procedure is first to model the attached exciter as an additional degree of freedom system and next to verify the suggested model by experimentally extracting the natural frequencies of the test structure with various values of exciter mass, stinger stiffness and attachment position of the exciter on the test structure. It is concluded that as additional degree of freedom system which includes the natural frequency of the exciter itself and axial stiffness of stinger should be considered to quantatively define the coupling effects of structure-exciter interaction on the measured natural frequencies. It is not the mass of the exciter itself but the coupling effect of the additional degree of freedom mass-spring system consisting of exciter body and armature coil that characterizes the natural frequency deviation. Therefore, when the natural frequency of this additional mass-spring system is outside of the test frequency range, the coupling effect of structure-exciter interaction can be minimized.

• 수산해양기술연구
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• 제40권3호
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• pp.232-243
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• 2004

After studying the composition about the torsional shafting of main engine for fishing vessel with Power Take Off (PTO) System, the authors made a computer program using the transfer stiffness coefficient method (TSCM) for analyzing torsional vibration about the shafting with PTO system and nonlinear elastic coupling. The torsional shafting of main engine was separated by 3 types according to the connecting. The torsional shafting of main engine was separated by 3 types according to the connecting condition of main engine with propeller or the PTO system or both of them. In this paper, the change of natural frequencies and natural modes according to connecting condition of torsional shafting and nonlinear elastic coupling were analyzed. The accuracy of the TSCM was confirmed by comparing with the computational results of the Finite Element Method.

• 한국공간구조학회논문집
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• 제18권4호
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• pp.97-104
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• 2018

A connected control method for the adjacent buildings has been studied to reduce dynamic responses. In these studies, seismic loads were generally used as an excitation. Recently, multi-hazards loads including earthquake and strong wind loads are employed to investigate control performance of various control systems. Accordingly, strong wind load as well as earthquake load was adopted to evaluate control performance of adaptive smart coupling control system against multi-hazard. To this end, an artificial seismic load in the region of strong seismicity and an artificial wind load in the region of strong winds were generated for control performance evaluation of the coupling control system. Artificial seismic and wind excitations were made by SIMQKE and Kaimal spectrum based on ASCE 7-10. As example buildings, two 20-story and 12-story adjacent buildings were used. An MR (magnetorheological) damper was used as an adaptive smart control device to connect adjacent two buildings. In oder to present nonlinear dynamic behavior of MR damper, Bouc-Wen model was employed in this study. After parametric studies on MR damper capacity, optimal command voltages for MR damper on each seismic and wind loads were investigated. Based on numerical analyses, it was shown that the adaptive smart coupling control system proposed in this study can provide very good control performance for Multi-hazards.

• The Korean Journal of Physiology and Pharmacology
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• 제2권1호
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• pp.21-30
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• 1998

The effects of GABA and glutamate on the horizontal cells were explored by an intracellular recording method to discern the mechanisms of receptive field formation by chemical coupling in the catfish outer retina. The results suggest that the horizontal cells of the catfish retina might use GABA as their transmitters and that the GABAergic system contributes to the formation of receptive fields of the horizontal cells. GABAC receptors may be involved in a chemical coupling between horizontal cells and concerned with the depolarizing actions by GABA on horizontal cells in the catfish retina. Since the chloride equilibrium potential is more positive than the dark membrane potential in horizontal cells, GABA released from a horizontal cell may depolarize the neighboring horizontal cells. Thus a chemical coupling between horizontal cells may be formed. $GABA_A$ receptors also may be involved in the negative feedback mechanism between photoreceptor and horizontal cell. And glutamate may be involved in connecting positive and negative feedback systems since it potentiated the GABA's actions. Therefore, it is presumed that large receptive fields in the catfish retina are formed not only by electrical coupling but also by chemical coupling between horizontal cells. And information travels laterally by pathways involving both electrical coupling composed of gap junctions and chemical coupling in the retinal network.

• 한국정밀공학회지
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• 제23권5호
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• pp.128-136
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• 2006

To predict the noise and vibration characteristics of induction motor system, it is necessary to develop the mathematical model including all the mechanical elements such as shaft, blower, rotor, fan, bearing, case and mounting parts. Coupling effect between case-mount system and rotor- shaft system including shaft, blower, rotor, fan and bearing is examined. Impact exciting experimentation was done in order to verify vibration model of the induction motor system. From experimental results, we can appreciate that the natural frequencies of induction motor system are in good agrements with analysis.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2000년도 제31회 춘계학술대회
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• pp.3-10
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• 2000

The undesired situation of development of tribology and its reason is analyzed. The problem comes from insufficient study on the concept system and method system, which can match the name, definition and nature of tribology. The existence of three axioms in tribology is discussed. They are axiom of system dependent, axiom of time dependent and axiom of coupling of behaviors of multi-discipline. A series of lemmas has been deduced from three axioms. It is expected that they can be a foundation to establish the concept system and method system.

• Journal of electromagnetic engineering and science
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• 제7권3호
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• pp.134-137
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• 2007

This paper presents the design of the compact UHF Bandpass filter of CT-type with a novel mixed coupling topology. In further detail, this new coupling structure mathematically equals the transmission zero that enables particularly the better rejection performance in the stopband without increasing the filter's order. To envision this design concept, we fabricated a microstrip filter whose measurement proves to agree with the predicted performance and the suggested coupling structure reduces the overall size, and will be possibly used in the miniaturized UHF apparatus such as the RFID system.