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Research Area
Robust<br />
Control

Robust
Control

Robust control is a branch of control theory whose approach to controller design explicitly deals with uncertainty.
Time Delay<br />
System

Time Delay
System

Systems with time-delays are called time-delay systems. Controls of time delay systems are more complicated compared to ordinary systems.
Adaptive<br />
Filter

Adaptive
Filter

An adaptive filter is a system with a linear filter that has a transfer function controlled by variable parameters and a means to adjust those parameters according to an optimization algorithm.
Image<br />
Processing

Image
Processing

Image processing is processing of images using mathematical operations by using any form of signal processing for which the input is an image.
LATEST publication
  • H∞ control for singular Markovian jump systems with incomplete knowledge of transition probabilities

    Nam Kyu Kwon, In Seok Park, PooGyeon Park

    Applied Mathematics and Computation

    AbstractThis paper proposes a H∞ state-feedback control for singular Markovian jump systems with incomplete knowledge of transition probabilities. Different from the previous results where the transition rates are completely known or the bounds of the unknown transition rates are given, a more general situation where the transition rates are partly unknown and the bounds of the unknown transition rates are also unknown is considered. Moreover, in contrast to the singular Markovian jump systems studied recently, the proposed method does not require any tuning parameters that arise when handling non-convex terms related to the mode-dependent Lyapunov matrices and the corresponding self-mode transition rates. Also, this paper uses all possible slack variables related to the transition rates into the relaxation process which contributes to reduce the conservatism. Finally, two numerical examples are provided to demonstrate the performance of H∞ mode-dependent control.
  • A combined reciprocal convexity approach for stability analysis of static neural networks with interval time-varying delays

    Won Il Lee, Seok Young Lee, PooGyeon Park

    Neurocomputing

    AbstractThis paper proposes a novel approach called a combined reciprocal convexity approach for the stability analysis of static neural networks with interval time-varying delays. The proposed approach deals with all convex-parameter-dependent terms in the time derivative of the Lyapunov-Krasovskii functional non-conservatively by extending the idea of the conventional reciprocal convexity approach. Based on the proposed technique and a new Lyapunov-Krasovskii functional, two improved delay-dependent stability criteria are derived in terms of linear matrix inequalities(LMIs). Some numerical examples are given to demonstrate the proposed results.
  • Polynomials‐based summation inequalities and their applications to discrete‐time systems with time‐varying delays

    Seok Young Lee, Won Il Lee, PooGyeon Park

    International Journal of Robust and Nonlinear Control

    AbstractThis paper proposes a novel summation inequality, say a polynomials-based summation inequality, which contains well-known summation inequalities as special cases. By specially choosing slack matrices, polynomial functions, and an arbitrary vector, it reduces to Moon's inequality, a discrete-time counterpart of Wirtinger-based integral inequality, auxiliary function-based summation inequalities employing the same-order orthogonal polynomial functions. Thus, the proposed summation inequality is more general than other summation inequalities. Additionally, this paper derives the polynomials-based summation inequality employing first-order and second-order orthogonal polynomial functions, which contributes to obtaining improved stability criteria for discrete-time systems with time-varying delays.
LATEST project
ABOUT LABORATORY

Signal Processing and Control Laboratory has been organized since 1996. Our current research interests include convex optimization theories and their applications in control, estimation and signal processing.
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