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This paper presents a simple approach for facial expression recognition. In the preprocessing stage, rough lips region is obtained from original face image using HSI space. Then, based on the binary image, exact lips region is located within a rectangle. To achieve this goal, PSO algorithm is applied to search for the best rectangle region. Finally, expression is estimated based on the parts ratio of lips. The simulation results show that this geometric approach is accurate and effective, even for the slightly smile.

This paper presents an automatic approach for facial expression deformation. In order to guarantee the expression deformation is dealt with high quality and conveniently, the approach uses two key technologies: the PSO detection and the affine transformation. The simulation results show that this method can produce natural smile expression, without marking the spots manually, especially works well for some shy smile expressions.

A generating algorithm for parametric curve based on ant colony optimization is proposed in this paper. In order to produce the maximum step efficiently, the ant colony optimization is used to search the optimal step of curve in forward. Based on ant colony optimization, curve generating algorithm can search for the optimal step of parametric curve with any order quickly. Comparison of optimal step value between the proposed algorithm and other methods is also performed. Simulation results show the effectiveness of the proposed method. Since there is no restriction on control point position and curve order, the algorithm can be extended easily to other parametric curves besides Bézier curves.

A class of stochastic nonlinear systems with unknown bounded parameters and zero dynamics are considered in this paper. By a series of coordinate changes, the original system is re-parameterized, which is suit for using the reduced-order observer and 1-dimension adaptive law to reduce the dynamic order of closed-loop system. In adaptive backstepping design, the quadratic and the quartic Lyapunov functions are presented simultaneously to reduce the static order of nonlinearities. It is shown that all the solutions of the closed-loop system are regulated to an arbitrarily small neighborhood of the origin in probability. Due to the order reduction of the controller, the design scheme in this paper has more practical values. A simulation example demonstrates the control scheme.

This paper focuses on the robust passive control problem of singular systems with uncertainties which is described by state space. Specifically the impulse of the singular systems is considered. We develop a linear matrix inequality (LMI) approach for designing the robust impulse passive state feedback controller and the output feedback controller such that the closed-loop system is quadratically stable, strictly passive and impulse free for all the admissible uncertainties. Finally, we testify the feasibility of the theorems by the numerical examples.