• 한국컴퓨터정보학회논문지
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• 제12권3호
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• pp.75-84
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• 2007

웹 어플리케이션의 복잡도는 증가하고 생명주기는 점차 짧아지는 추세이다. 따라서 웹 어플리케이션의 유연성과 확장성을 향상시키는 재구조화가 필요하며, 클러스터링을 통해 시스템을 이해하고 재구조화하는 접근법이 사용되고 있다. 본 논문에서는 웹 페이지들을 클러스터링하기 위한 결합도 메트릭을 제안한다. 이를 위하여 웹 어플리케이션 모델을 정의하였으며 이 모델에는 웹 페이지 사이의 관계 유형 및 파라미터의 개수 정보가 포함된다. 이를 기반으로 결합도 메트릭은 웹 페이지 사이의 직접적인 연결 강도와 간접적인 연결 강도를 고려하여 정의되었다. 두 페이지 사이에 직접적인 관계가 다수 존재하고 파라미터의 개수가 많을수록 직접적인 연결 강도는 높아지며, 두 페이지가 각각 다른 페이지들에 대해 가지는 연결 패턴이 유사할수록 간접적 연결 강도는 높아진다. 제안한 메트릭을 메트릭 검증 프레임웍을 이용하여 검증하고, 예제에 적용하여 기존 메트릭과의 비교 분석을 통하여 기존 메트릭의 단점을 보완하였음을 보인다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국제학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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• pp.1014-1017
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• 1988

Direct-drive robots have excellent features including no backlash, small friction, and high mechanical stiffness. However, dynamic coupling among joints as well as nonlinear effects become more prominent than traditional robots with reducers. Another critical issue is that the robot becomes more sensitive to the change of load. In this paper, we develop a simple current feedback scheme for reducing the influence of dynamic coupling and load sensitivity on the direct-drive robots. The method is implemented on a 2 d.o.f. planar direct-drive robot. Then the validity of the method is demonstrated through experiments.

• 한국자기학회지
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• 제6권1호
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• pp.15-20
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• 1996

Co/Pd와 Co/Pd 다층박막으로 구성된 이중막 시스템에서 direct overwriting을 구현하는데 필수적인 교환결합 (exchange coupling)에 대하여 연구하였다. Co/Pd 및 Co/Pd 다층박막을 수직자성을 가지도록 하기 위하여 Co층의 두께를 4- .angs. 이하로 하여 전자빔 증착법으로 제작한 후 x-ray 회절 실험으로 구조 분석을 하였고, Kerr spectrometer, VSM을 사용하여 자기 및 자기광학적 성질을 조사하였다. 기억막과 기준막으로 구성된 이중막에서는 exchange coupling이 커서 자화반전이 두 박막에서 동시에 일어나며, 두 박막사이에 적당한 두께의 비자성 사이막(non-magnetic spacer)이 존재하는 경우에는 두 박막사이의 교환결합의 크기가 줄어들어서 두 박막의 자화반전이 분리되어 계단식 자화곡선이 생겼다. 또 비자성 사이막이 두꺼우면 두 박막사이의 교환결합이 사라짐이 관찰 되었다. 두 박막사이의 교환결합은 자구 기록 실험을 통해서도 그 존재를 확인할 수 있었다.

• BMB Reports
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• 제31권1호
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• pp.95-100
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• 1998

Two innovative methods to prepare target-sensitive immunoliposomes containing doxorubicin by coupling monoclonal antibodies (mAb DH2, SH1) specific to cancer cell surface antigens ($G_{M3}$, $Le^X$) have been developed and are described here. Firstly, liposomes containing N-glutaryl phosphatidylethanolamine (NGPE) were prepared, followed by the encapsulation of doxorubicin, DH2 or SH1 antibodies were conjugated to NGPE in the liposomes (direct coupling). Secondly, liposomes were prepared with NGPE/mAb conjugates by the detergent dialysis method (conjugate insertion), and then doxorubicin was encapsulated by proton gradient. The immunoliposomes prepared by both methods were able to specifically bind to the surface of the tumor cells - B16BL6 mouse melanoma cells. The efficiencies of doxorubicin-entrapping into liposomes prepared by direct coupling and conjugate insertion was about 98% and 25%, respectively. These types of liposomal formulation are sensitive to target cells, which can be useful for various clinical applications.

• 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.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.156.1-156
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• 2001

It is observed that if the 2-gimballed seeker is stabilized using rate gyros mounted along its primary axis, line of sight change measured in the seeker is induced by the rolling due to the bank-to-turn(BTT) steering as well as the actual change. This body-coupling within BTT homing includes the spurious target maneuver effect and the coupling loop due to the rate gyro misalignment. In this paper we formulates the linear BTT homing loop model with a 2-gimballed seeker including those body-coupling effects. With the model, we analyze the effects of the couplings, and show that the roll rate coupling to the rate gyro for the stabilztion of gimbal could seriously deteriorate the homing loop stability. And we propose a direct linear compensator for the coupling to recover the stability.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 추계학술대회논문집 - 한국공작기계학회
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• pp.140-143
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• 2000

Motion control system using motor generally consists of 2 inertio system, motor inertio and load inertio linked with flexible coupling. In the case of direct drive motor control, the effect of coupling inertio decrease the precision performance. The study is about semiclosed control scheme of the system and experimental setup. To compensate the effect of coupling inertio, semiclosed control system by disturbance observer is employed. The simulation result is shown.

• Bulletin of the Korean Chemical Society
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• 제16권5호
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• pp.427-432
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• 1995

A model based on two coupled generalized Langevin equations is proposed to investigate the trans-stilbene photoisomerization dynamics. In this model, a system which has two independent coordinates is considered and these two system coordinates are coupled to the same harmonic bath. The direct coupling between the system coordinates is assumed negligible and these two coordinates influence each other through the frictional coupling mediated by solvent molecules. From the Hamiltonian which is equivalent to the coupled generalized Langevin equations, we obtain the transition state theory rate constants of the stilbene photoisomerization. The rates obtained from this model are compared to experimental results in n-alkane solvents.

• Journal of Power Electronics
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• 제18권6호
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• pp.1634-1641
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• 2018

This study focuses on a high-performance direct active and reactive power controller design that is successfully applicable to three-phase pulse width modulation (PWM) AC/DC converters used in renewable distributed energy generation systems. The proposed controller can overcome the sluggish transient dynamic response of conventional controllers to rapid power command changes. Desired active and reactive powers can be thoroughly obtained at the end of each PWM period through a deadbeat solution. The proposed controller achieves an exact nonlinear cross-coupling decoupling of system power without using a predefined switching table or bang/bang hysteresis control. A graphical and analytical analysis that naturally leads to a control voltage vector selection is provided to confirm the finding. The proposed control strategy is evaluated on a 3 kW PWM AC/DC converter in the simulation and experiment.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1169-1177
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• 2008

The system of the railway signaling using the track transmits the approved speed to the location of a train and it. Referring to the way of transmitting train control information, there are the one transmitting it to the on-board system of a train using the direct track, the another transmitting it establishing an instrument, and the other transmitting an instrument by a railway track. The one is the method using the direct track as a conductor for composing the part of the track and attaining the information controlling a train by transmitting a signal to the track. It is used for the high-speed railway and the subway. The method using the track attains information by transmitting it to returned information, and the on-board system of a train attains it by magnetic coupling. Because many reinforcing bars on the concrete slab track are used, interaction between a rail and a reinforcing bar that is not produced on ballast track is made. Due to the interaction, the electric characteristic of rail is changed. In the current paper, we numerically computed the coupling coefficient between the rail and the reinforcing bar based on the concrete slab track throughout the model related to the rail and the reinforcing bar using the concrete slab track that is used in the second interval of the Gyeongbu high-speed railway, and we defined the coupling coefficient not changed in the electric characteristic of rail in the condition that there is no interaction between the rail and the reinforcing bar.