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New approaches are proposed for complex industrial process monitoring and fault diagnosis based on kernel independent component analysis (KICA) and sparse support vector machine (SVM). The KICA method is a two-phase algorithm: whitened kernel principal component analysis (KPCA). The data are firstly mapped into high-dimensional feature subspace. Then, the ICA algorithm seeks the projection directions in the KPCA whitened space. Performance monitoring is implemented through constructing the statistical index and control limit in the feature space. If the statistical indexes exceed the predefined control limit, a fault may have occurred. Then, the nonlinear score vectors are calculated and fed into the sparse SVM to identify the faults. The proposed method is applied to the simulation of Tennessee Eastman (TE) chemical process. The simulation results show that the proposed method can identify various types of faults accurately and rapidly.

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This paper investigates the adaptive fault-tolerant control problem for a class of nonlinear systems with unknown control directions and uncertain parameters. To solve this control problem, the homogeneous domination method based on backstepping and fault-tolerant control scheme is applied to the uncertain nonlinear systems. First, a homogeneous domination-based adaptive control scheme using Nussbaum-type function is designed. Then, a fault-tolerant controller is proposed to deal with the actuator faults. The adaptive controller ensures that the closed-loop system is bounded, and all the states of the system asymptotically converge to 0. Finally, a simulation example is applied to demonstrate the effectiveness of the new designed adaptive fault-tolerant control scheme.

The problem of delay-dependent robust H ∞ control for T-S fuzzy descriptor networked control systems with multiple state time-delays is investigated. First, in terms of linear matrix inequality (LMI) approach, an improved delay-dependent criterion is established to ensure that the descriptor system is regular, impulse free and stable with H ∞ performance. Without using model transformation and bounding technique for cross terms, the criterion is less conservative. With the proposed criteria, we are able to obtain maximum allowable delay bound (MADB) of NCS. Numerical example shows that the proposed criteria are effective and less conservative.