• Journal of the Korean Society for Precision Engineering
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• v.16 no.6
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• pp.166-175
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• 1999

This paper describes a design and performance evaluation of robust controller which overrides unstable motion and pulls out quickly after water entry of underwater vehicle dropped from aircraft or surface ship. We use 6-DOF equation for model of motions and assume parameter uncertainty to reflect the difference of real motion from modelled motion equation. we represent a nonlinear system with uncertainty as Takagi and Sugeno's(T-S) fuzzy models and design controller stabilizing them. The fuzzy controller utilizes the concept of so-called parallel distributed compensation (PDC). Finally, we confirm stability and performance of the controller through computer simulation and hardware in the loop simulation (HILS).

• Proceedings of the Korean Information Science Society Conference
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• 2007.10d
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• pp.613-618
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• 2007

현재 하나의 TV에 연결할 수 있는 수많은 기기들이 개발, 판매되고 있다. 이렇게 연결하는 방법 중 현재 많이 사용하고 있는 방법 중에 하나인 HDMI의 경우에 HDMI-CEC라는 기능을 도입해서 연결된 각각의 기기를 따로따로 컨트를 하지 않고 하나의 리모컨으로 적용하는 방안을 제시하고 있다. 현재 가정에서 사용하는 DVD-Recorder에 HDMI-CEC 기능을 대응하여, 사용자가 원하는 기능을 여러 개의 기기를 직접 제어하는 것이 아니라, 단 하나의 키 동작으로 여러 개의 기기를 동시에 제어하는 시스템을 설계한다면 사용자에게 많은 편의를 줄 수가 있다. 그러나, 이러한 시스템을 설계했을 경우에 사용자가 원하는 동작을 정확히 안 하는 문제, 반응 속도가 너무 느려서 사용자가 동작을 안 하는 것으로 착각하게 만드는 문제와 HDMI-CEC의 Spec에서는 제시하고 있지 않으나 사용자의 편의물 위해서 지원해야 하는 경우가 있을 수 있다. 이 논문에서는 HDMI-CEC와 PDC의 spec에 대한 설명을 하고, HDMI-CEC를 적용한 시스템에 대한 설계를 한다. 그리고, 그 시스템에서 발견된 문제 중 정확한 동작을 하지 않는 TV가 꺼져있는 OnTouchPlay의 경우의 대한 처리와, 반응 속도가 느린 경우인 시스템을 부팅하는 경우의 반응시간을 줄이는 방안, 그리고 HDMI-CEC의 spec에는 없으나 사용자의 편의를 위해서 지원해야 하는 기능들에 대해 논한다.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.42 no.1
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• pp.13-21
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• 2005

This paper presents a fuzzy model-based approach for synchronization of time-delay chaotic system with input saturation. Time-delay chaotic drive and response system is respectively represented by Takagi-Sugeno (T-S) fuzzy model. Specially, the response system contains input saturation. Using the unidirectional linear error feedback and the parallel distributed compensation (PDC) scheme, we design fuzzy chaotic synchronization system and analyze local stability for synchronization error dynamics. Since time-delay in the transmission channel always exists, we also take it into consideration. The sufficient condition for the local stability of the fuzzy synchronization system with input saturation and time-delay is derived by applying Lyapunov-Krasovskii theory and solving linear matrix inequalities (LMI's) problem. A numerical example is given to demonstrate the validity of the proposed approach.

• Journal of the Korean Institute of Intelligent Systems
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• v.10 no.2
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• pp.152-160
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• 2000

This paper addresses the analysis and design of fuzzy-model-based controller for nonlinear systems using extended PDC and optimal pole-placement schemes. In the design procedure, we represent the nonlinear system using a Takagi-Sugeno fkzy model and formulate the controller rules by using the extended parallel distributed compensator (EPDC) and construct an overall fuzzy logic controller by blending all local state feedback controllers with an optimal pole-placement scheme. Unlike the commonly used parallel distributed compensation technique, by blending a newly extended parallel distributed compensator and the optimal poleplacement schemes, we can design not only a local stable k z y controller but also an overall stable fuzzy controller to perform the tacking control objective. Furthermore, a stability analysis is carried out not only for the fuzzy model but also for a real nonlinear system. Finally. the effectiveness and feasibility of the proposed fizzy model-based controller design method has been shown through a simulation example.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1846-1847
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• 2011

In this paper, for the trajectory tracking control of mobile robot, firstly, we obtained the T-S fuzzy models from the tracking-error models, one of which has nonlinear form and the other is linearized around the reference trajectory. Then the tracking control inputs are designed using the proposed fuzzy linearization method and the existed PDC method. Lastly, the tracking performance is tested and compared for each model through simulation.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1724_1725
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• 2009

In this paper, new approaches to optimal controller design for a class of discrete-time Takagi-Sugeno (T-S) fuzzy systems are proposed based on a relaxed approach, in which non-quadratic Lyapunov function and non-parallel distributed compensation (PDC) control law are used. New relaxed conditions and linear matrix inequality (LMI) based design methods are proposed that allow outperforming previous results found in the literature. Finally, an example is given to demonstrate the efficiency of the proposed approaches.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.227-230
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• 1998

In this paper, we propose the design method of fuzzy robust H$\infty$ controller for the uncertain nonlinear discete-time systems with time delay. First, we represent a nonlinear plant with a modified T-S(Takagi-Sugeno) fuzzy model. Then design method utilizing the concept of PDC (parallel distributed compensation) is employed. For the modified T-S fuzzy model with uncertainty and delay, the sufficient condition of the quadratic stabilization with an H$\infty$ norm bound is presented in terms of Lyapunov stability theory and fuzzy robust H$\infty$ controller design method is given by LMI(linear matrix inequality) approach. Also an illustrative example is given to demonstrate the result of the proposed method.

• Transactions on Control, Automation and Systems Engineering
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• v.1 no.1
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• pp.44-49
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• 1999

This paper presents a new T-S(Tae-Sugeno) fuzzy controller design method satisfying the output energy bound. Maximum output energy via a quadratic Lyapunov function to obtain the bound on output energy is derived. LMI(Linear Matrix Inequality) problems which satisfy an output energy bound for both of the continuous-time and discrete-time T-S fuzzy control system are also derived. Solving these LMIs simultaneously, we find a common symmetric positive definite matrix P which guarantees the global asymptotic stability of the system and stable feedback gains K's satisfying the output energy bound. A simple example demonstrates validity of the proposed design method.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.5
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• pp.43-54
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• 1997

The objective of this paper is to present a controller-design method that can guarantee the global stability for nonlinear systems described by takagi-sugeno fuzzy models, and to apply the method to a typical nonlinear control problem. The presented method gives us a compensated fuzzy controller through the following major steps: First, if each local linear model of a given takagi-sugeno fuzzy system does not have the same input matrix, the method expands the system into the one with a method finds a takagi-sugeno fuzzy controller guaranteeing the global stability of the closed loop via solving relevant linear matrix inequalities. Compared to the conventional PDC (paralled distributed compensation) technique, the presented method has an advantage that trial-and-errors to check the global stability are not necessary. An illustrative simulation on the control of inverted pendulum is performed to demonstrate the applicability of the presented method, and its results show that a controller satisfying the global stability and robustness can be obtained by the method.

• Textile Coloration and Finishing
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• v.21 no.4
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• pp.46-56
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• 2009

In order to establish the standard manufacturing condition of PET flame retardant sheets, physicochetnical properties of the samples made by the conventional flame-retardant finishing were systematically investigated, including compatibility among flame retardant agent and finishing auxiliaries, surface property, and wicking property. From this results, the addition of washing and renapping process after the shearing process was required for the more effective in producing PET flame-retardant sheet by the standard finishing. The effect of the modification of the regular flame retardant finishing process was studied by FTIR, TGA, and flame retardancy test.