• 대한전자공학회논문지
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• 제24권2호
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• pp.215-222
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• 1987

This paper generalizes the previous results of the closed-loop eigenstructure assignment via output feedback in linear multivariable systems. Necessary and sufficient conditions for the closed-loop eigenstructure assignment by output feedback are presented. Some known results on entire eigenstructure assignment are deduced from this results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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• pp.786-790
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• 1987

An optimization problem minimizing n given time-weighted performance index for discrete-time linear multi-input systems is investigated for the prespecified closed-loop eigenvalues. Necessary conditions for an optimality of the controller that satisfies the specified closed-loop eigenvalues are derived. A computational algorithm solving the optimal constant feedback gain is presented and a numerical example is given to show the effect of a time-weighted performance index on the transient responses.

• 대한전자공학회논문지TC
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• 제45권12호
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• pp.13-19
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• 2008

본 논문에서는 4개의 송신 안테나를 사용하는 새로운 폐루프 직교 시공간 블록 부호 (Closed Loop Orthogonal Space-Time Block Code) 기법을 제안하고 기존의 폐루프 기법들과 비트오율 (Bit Error Rate; BER) 성능을 비교한다. 제안된 기법은 송신기에서 폐루프 기법을 통하여 채널 정보를 귀환받고 심벌 결합기를 통해 변조 심벌들을 결합한 후 시공간 블록 부호화하여 송신 안테나로 전송한다. 그 결과, 제안된 기법은 기존의 폐루프 시공간 블록 부호 기법에 비해 귀환된 채널 정보를 보다 효율적으로 이용함으로써 최대의 채널 이득을 획득하는 동시에 full-rate을 만족한다. 또한 채널 행렬이 직교하므로 수신 심벌에 대한 선형적인 복호가 가능하며 수신기는 낮은 복호 복잡도를 갖게 된다. 모의실험 결과, 제안된 기법은 기존의 폐루프 기법들과 비교하여 성능 향상을 보임을 알 수 있다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1986년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 17-18 Oct. 1986
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• pp.86-89
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• 1986

This paper presents a design methodology for a PID regulator. The parameters of the PID regulator are determined through equivalent structure to the closed-loop system whose feedback gain assigns prescribed eigenvalues of the closed-loop system and minimizes a given performance index.

• 제어로봇시스템학회논문지
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• 제2권1호
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• pp.1-4
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• 1996

This paper presents a state feedback $H^{\infty}$ controller design method for linear systems with delayed states and inputs. We derive a sufficient condition that the closed-loop system is asymptotically stable for all time-delays and that the $H^{\infty}$-norm of the closed-loop transfer function is less than or equal to some prescribed level $\gamma$. And we propose a sufficient condition for the existence of a state feedback $H^{\infty}$ controller using a form of linear matrix inequality(LMI). Furthermore, we show that the state feedback $H^{\infty}$ controllers can be obtained from solutions satisfying LMI.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 A
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• pp.111-114
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• 2003

In this paper, we consider the stabilization and $H_\infty$ control of linear systems with static output feedback control. The static output feedback control represents the simplest closed-loop control that can be realized in practice, and, moreover, it is less expensive to be implemented and is more reliable. In spite of its advantages, it is one of the open problems which is not sloved analytically or numerically yet. After decompose the closed-loop system into feedback form, by adopting the small gain theorem, we obtain a sufficient condition for stabilization and a sufficient condition for It control expressed as linear matrix inequalites. Finally, we show the usefulness of our results by a numerical example.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1643-1646
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• 1997

In this study, the method is proposed, which enable us to noninvasively assess baroreflex sensitivity through the closed-loop feedback modle between RR flucturarion and arterial blood pressure fluctuation. The proposed indexes of baroreflex sensitivity, BRS$_{LF}$와 BRS$_{HF}$ are calculated by the modulus (or gain) of the transfer function between fluctuatuons in blood pressure and RR interval in the LF band HF band, where the coherence is more than 0.5 to evaluate the performance of the proposed method, it is applied to various cardiovascular variability signals obtained form subjects under the submaximal ecericse on bicycle ergometner. In result it is concluded that the proposed method can noninvasively assess the baroreflex sensitivity.ty.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 D
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• pp.1162-1164
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• 1997

This paper presents a power system stabilizer(PSS) using sliding mode-model following(SM-MF) including closed-loop f:edback(CLF) and compares the SM-MF PSS without CLF with that including CLF. The aim of this SM-MF PSS including CLF is to damp the low-frequency oscillation by using CLF and then is to obtain asymptotic tracking error between the reference model state and the plant state.

• 소음진동
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• 제4권2호
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• pp.177-185
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• 1994

In this study, the effect of parameter errors on the closed-loop behavior of flexible structure is analyzed for IMSC(Independent Modal Space Control) with PPF(Positive Position Feedback). If the control force designed on the basis of structure model with the parameter errors is applied to control the actual system, the closed-loop performance of the actural system will be degraded depending on the degree of the errors. An asymptotic stability condition has been derived, using Lyapunov approach, which is independent of the dynamic characteristics of the structure being controlled. The extent of deviation of the closed-loop performance from the designed one is also derived and evaluated using operator techniques. It has been found that the extent of the deviation is proportational to the magnitude of the parameter errors, and that the proportional coefficient depends on the control algorithm.

• International Journal of Control, Automation, and Systems
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• 제3권1호
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• pp.109-116
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• 2005

The design of reconfiguring a class of second-order dynamic systems via proportional plus derivative (P-D) feedback is considered. The aim is to resynthesize a P-D feedback controller such that the eigenvalues of the reconfigured closed-loop system can completely recover those of the original close-loop system, and make the corresponding eigenvectors of the former as close to those of the latter as possible. Based on a parametric result of P-D feedback eigenstructure assignment in second-order dynamic systems, parametric expressions for all the P-D feedback gains and all the closed-loop eigenvector matrices are established and a parametric algorithm for this reconfiguration design is proposed. The parametric algorithm offers all the degrees of design freedom, which can be further utilized to satisfy some additional performances in control system designs. This algorithm involves manipulations only on the original second-order system matrices, thus it is simple and convenient to use. An illustrative example and the simulation results show the simplicity and effect of the proposed parametric method.