Synchronization of hyper-chaotic Lorenz system and its application in secure communication is studied. Based on the Lyapunov stability, an active nonlinear controller is presented to achieve synchronization of the drive system and the response system. By the conversion functions, the useful signal is modulated into the drive system, and then a secure communication based on hyper-chaotic masking is derived, which can quickly recover the useful signal from the receiver system. Simulation results illustrate the effectiveness of the proposed method.

A multi-point wireless pulse measuring system based on CC2530 is discussed. By using a PVDF pressure sensor, human pulse signal is picked up. Then a filter circuit and a amplification circuit are designed to obtain accurate and stable signal. Based on single-point pulse measuring, multi-point wireless pulse measuring system based on CC2530/ZigBee network is constructed, and a data managing system based on LabVIEW is designed to deal with these signals. Finally, experiment is provided to show the effectiveness of the proposed scheme. Keywords: Pulse; CC2530; ZigBee; LabVIEW; PVDF

This paper introduces a design of intelligent smartcar system based on MCU SPCE061A and MCU 89S52. The practical path images are obtained using by the CCD camera, then a double P control method is applied to dynamically adjust steering angle. Based on fuzzy relationship between angle and velocity, the PD controller is proposed to achieve path identification and arbitrary track. Experiments show that the response and stability of the proposed system are excellent.

A sliding mode controller for buck converter based on PWM technology is discussed.Firstly, the schematic diagram of buck converter circuit based on a slidingmode control strategy is designed. Then a sliding mode control approach basedon reaching law is constructed. A circuit model based on MULTISIM is proposed.Finally, the simulation result show that the proposed method can effectively improvethe system dynamic characteristics.

An adaptive controller with adaptive rate is presented to synchronize two chaos systems and to apply to secure communication. Based on Lyapunov stability theory, a sufficient condition and adaptive control parameters are obtained. Finally, the simulation with synchronization and secure communication is given to show the effectiveness of the proposed method. Keywords: adaptive; synchronization; observer; controller.