Kuang Lian - Academia.edu (original) (raw)

Papers by Kuang Lian

IFAC Proceedings Volumes, 2008

This paper proposes an integral Takagi-Sugeno (T-S) fuzzy controller to achieve the output voltag... more This paper proposes an integral Takagi-Sugeno (T-S) fuzzy controller to achieve the output voltage regulation for an AC-DC isolated active high power factor correction (AHPFC) converter. The converter can avoid high voltage stresses and decrease harmonic distortions under discontinuous conduction mode (DCM). The dynamics of the converter are derived by the AM-TTS-DS method. To ensure zero steady-state error, we add an extra integral error signal to the dynamics. Translating coordinate to the DC operating points, the converter's stabilization model can be determined. Both feedback gains and system stability are inferred simultaneously. The control gains can be obtained by solving linear matrix inequalities (LMIs) via Matlab's toolbox. A surprising property is that the obtained feedback gains are identical for every fuzzy control rule. This condition greatly simplifies the realization using analog circuits. The simulations and experimental results exhibit the satisfactory performance of the converter with the designed integral T-S fuzzy regulator.

IFAC Proceedings Volumes, 2005

In this paper,we propose a low effort control scheme for chaotic systems by using fuzzy model-bas... more In this paper,we propose a low effort control scheme for chaotic systems by using fuzzy model-based design method. First, we represent nonlinear systems into T-S fuzzy models in a working region covering the point to be regulated. The stability condition of the overall system is formulated into (LMIs). To guarantee the stability, the region of attraction is also investigated. According to topologically transitive property for chaotic systems, the feedback control force is activated only when the trajectory passes through the neighboring region of the regulated point. Compared to purely fuzzy model-based controller, the control force for the fuzzy chaos hybrid controller is extremely low.

IFAC Proceedings Volumes, 2002

IEEE Transactions on Control Systems Technology, 2005

ABSTRACT

IEEE Transactions on Automatic Control, 1994

... 0 This theorem will be directly used in the following sections to prove the controllability o... more ... 0 This theorem will be directly used in the following sections to prove the controllability of the spacecraft system by using gas jets. 2 TI ~ ~ following prod is maidy based OU =U unpuhlislted mte of W. P. Dayawausa. 4 Controllability ...

IEEE Access

The degenerate unmixing estimation technique (DUET), enables facile sound source separation throu... more The degenerate unmixing estimation technique (DUET), enables facile sound source separation through two signal mixtures. However, in numerous practical situations, identifying peaks in DUET histograms is difficult, which in turn prevents effective source separation. Specifically, sound sources with short time percentages in mixtures are more unlikely to form peaks in a histogram. Besides, when the noise floor of mixtures is high, the height of the histogram peak may be reduced, which causes peak position bias and prevents effective source separation. In this study, unique methods are proposed to solve the aforementioned problems. A subhistogram is established for each time frame; thus, the original histogram is divided into a series of subhistograms. Two measurement indices are then proposed to identify the accurate attenuation and delay parameters for sound sources: maximum distribution, which is based on the infinity norm, and variance distribution, which is based on variances. The results verify that maximum distribution effectively highlights the peaks of instantaneous sound sources when the time percentage difference between sound sources is excessively high. In this scenario, the conventional histogram is unable to find the peaks. When a strong noise disturbance is present in mixtures, variance distribution can be employed to estimate peak positions with lower biases than those in the conventional histogram. In addition to more well-defined and intense peaks, the proposed method can also reduce the bias error by 71% when the SNR is 0 dB. Variance distribution is more robust against noise disturbance compared to conventional histograms and can be adopted in a wide range of applications. INDEX TERMS Attenuation and delay histogram, Blind source separation, DUET, Instantaneous sound sources, W-disjoint orthogonality.

Journal of Marine Science and Technology

Sensors

This paper focuses on the development of a real-time wearable assist system for upper extremity t... more This paper focuses on the development of a real-time wearable assist system for upper extremity throwing action based on the accelerometers of inertial measurement unit (IMU) sensors. This real-time assist system can be utilized to the learning, rectification, and rehabilitation for the upper extremity throwing action of players in the field of baseball, where incorrect throwing phases are recognized by a delicate action analysis. The throwing action includes not only the posture characteristics of each phase, but also the transition of continuous posture movements, which is more complex when compared to general action recognition with no continuous phase change. In this work, we have considered six serial phases including wind-up, stride, arm cocking, arm acceleration, arm deceleration, and follow-through in the throwing action recognition process. The continuous movement of each phase of the throwing action is represented by a one-dimensional data sequence after the three-axial ac...

Ecotoxicology and Environmental Safety

It is highly significant to develop efficient soft sensors to estimate the concentration of hazar... more It is highly significant to develop efficient soft sensors to estimate the concentration of hazardous pollutants in a region to maintain environmental safety. In this paper, an air quality warning system based on a robust PM2.5 soft sensor and support vector machine (SVM) classifier is reported. The soft sensor for the estimation of PM2.5 concentration is proposed using a novel approach of Bayesian regularized neural network (BRNN) via forward feature selection (FFS). Zuoying district of Taiwan is selected as the region of study for implementation of the estimation system because of the high pollution in the region. Descriptive statistics of various pollutants in Zuoying district is computed as part of the study. Moreover, seasonal variation of particulate matter (PM) concentration is analyzed to evaluate the impact of various seasons on the increased levels of PM in the region. To investigate the linear dependence of concentration of different pollutants to the concentration of PM2.5, Pearson correlation coefficient, Kendall's tau coefficient, and Spearman coefficient are computed. To achieve high performance for the PM2.5 estimation, selection of appropriate forward features from the input variables is carried out using FFS technique and Bayesian regularization is incorporated to the neural network system to avoid the overfitting problem. The comparative evaluation of performance of BRNN/FFS estimation system with various other methods shows that our proposed estimation system has the lowest mean square error (MSE), root mean square error (RMSE), and mean absolute error (MAE). Moreover, the coefficient of determination (R-squared) is around 0.95 for the proposed estimation method, which denotes a good fit. Evaluation of the SVM classifier showed good performance indicating that the proposed air quality warning system is efficient.

Ultrasonics Sonochemistry

A novel electrochemical sensor using reduced graphene oxide (RGO) decorated marsh marigold-like z... more A novel electrochemical sensor using reduced graphene oxide (RGO) decorated marsh marigold-like zinc oxide (ZnO) nanocomposite for the detection of hydroquinone (HQ) is detailed in this paper. We have adopted an ecofriendly preparation procedure for the synthesis of RGO and the synthesis of marsh marigold-like ZnO is carried out using aqueous solution method. The RGO/ZnO nanocomposite is prepared based on ultrasonication technique using a high-intensity ultrasonic bath DC200H (200 W/cm2, 40 kHz) and is followed by its precise fabrication on glassy carbon electrode (GCE). Characterizations including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, and UV visible spectroscopy of ZnO nanoparticles, RGO, and RGO/ZnO nanocomposite are analyzed in this work. Different electrochemical studies were performed in this work to investigate performance of the proposed electrochemical sensor and cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques are used to achieve this. The oxidation and reduction peak currents of RGO/ZnO modified GCE exhibited sharp peaks at very low potential of 0.13 V and 0.06 V respectively. We have obtained a high sensitivity of 8.08 μA μM−1 cm−2, ultra-low limit of detection (LOD) value of 0.01 μM, and a broad linear range of 0.1–92 μM for the proposed sensor. Moreover, the fabricated sensor exhibited excellent selectivity, good reproducibility, stability, and repeatability revealing the high efficiency of the proposed sensor. Furthermore, experiments were conducted to examine the practical feasibility of the developed sensor. The electrochemical studies conducted as part of the work shows that RGO/ZnO nanocomposite is an apt material for the highly sensitive and efficient detection of HQ.

Inorganic Chemistry Frontiers

Electrochemical determination of hydroquinone based on a f-MWCNT decorated ruskin michelle-like Z... more Electrochemical determination of hydroquinone based on a f-MWCNT decorated ruskin michelle-like ZnO nanocomposite.

IFAC Proceedings Volumes

In this paper, a sensorless speed control for linear induction motors (LIMs) is developed based o... more In this paper, a sensorless speed control for linear induction motors (LIMs) is developed based on fuzzy observer design. First, the LIMs is represented by a Takagi-Sugeno (T-S) fuzzy model. Next, the fuzzy observer is constructed to estimate the immeasurable states of mover speed and secondary flux, where the observer gains are obtained by solving a set of linear matrix inequalities (LMIs). To overcome the high nonlinearity, a two stage approach is applied to design the control law. Then, exponential convergence for both estimation error and tracking error is concluded. This indicates that the proposed sensorless controller possesses the feature of fast transient response and high robustness. Finally, simulations and experiments are carried out to verify the theoretical results and show satisfactory performance.

2007 IEEE International Conference on Control Applications, 2007

... CH Liu is currently a lecturer in Department of Avionics in the China Institute of Technology... more ... CH Liu is currently a lecturer in Department of Avionics in the China Institute of Technology, Hsinchu, 31241, Taiwan and also works toward the Ph.D. degree in Department of Electrical ... The inferred output of the PDC controller is with the following form: τ(k) = r ∑ i=1 viKi x(k) (8) ...

2010 IEEE International Conference on Robotics and Automation, 2010

ABSTRACT In this paper, a sensorless speed controller for linear induction motor (LIM) is develop... more ABSTRACT In this paper, a sensorless speed controller for linear induction motor (LIM) is developed based on a fuzzy observer. First, the LIM is represented by a T-S fuzzy model. Next, the fuzzy observer is constructed to estimate the immeasurable states including the mover speed and secondary flux, where the observer gains are obtained by computationally solving a set of linear matrix inequalities. Based on the fuzzy observer, the synthesis using the virtual desired variable concept is applied to design the control law. Then, the exponential convergence for both estimation error and tracking error is concluded. This indicates that the proposed sensorless speed control possesses the feature with fast transient response and high robustness. Finally, experiments are carried out to verify the theoretical results and show satisfactory performance.

Studies in Fuzziness and Soft Computing, 2006

Discrete Dynamics in Nature and Society, 2014

We demonstrate an improved stability analysis based on a partition oriented technique for discret... more We demonstrate an improved stability analysis based on a partition oriented technique for discrete-time systems with interval time-varying delay. The partition oriented technique introduces beneficial terms contributing to the negative definiteness of the Lyapunov function difference, meanwhile completely avoiding traditional inequality based approaches. In contrast, nonpartitioning oriented techniques do not put emphasis on further dividing the interval of the summation in the Lyapunov function. Herein, we demonstrate that the advantages of exploiting partitioning techniques manifest the relaxed stability criteria, as well as the flexibility to tune tradeoff between allowable timedelay range performance and computational load. Simulation carried out on a benchmark discrete-time system reveals the significant improvement in terms of maximum allowable upper bound in comparison.

International Journal of Fuzzy Systems, 2015

ABSTRACT A novel online hybrid direct/indirect adaptive Petri fuzzy neural network (PFNN) control... more ABSTRACT A novel online hybrid direct/indirect adaptive Petri fuzzy neural network (PFNN) controller with stare observer for a class of multi-input multi-output (MIMO) uncertain nonlinear systems is developed in the paper. By using the Lyapunov synthesis approach, the online observer-based tracking control law and the weight-update law of the adaptive hybrid intelligent controller are derived. According to the importance and viability of plant knowledge and control knowledge, a weighting factor is utilized to sum together the direct and indirect adaptive PFNN controllers. In this paper, we prove that the proposed online observer-based hybrid PFNN controller can guarantee that all signals involved are bounded and that the system outputs of the closed-loop system can track asymptotically the desired output trajectories. An example including four cases is illustrated to show the effectiveness of this approach.

2014 IEEE International Conference on Consumer Electronics - Taiwan, 2014