The traditional multi-threshold image segmentation method has high complexity and the results are poor. In order to solve the problems, a new multi-thresholding method based on combining Fisher criterion and potential function was proposed. First, the Fisher criterion function was simplified and a recursive algorithm was used to reduce the computational complexity. Then the number of segmentation class was obtained by utilizing the histogram potential function method. Finally, the simplified Fisher criterion function was used for multi-thresholding and the segmentation results were further processed. The experimental results show that compared with the traditional multi-thresholding methods, the proposed method has better segmentation performance and that its running time is less. It can be used in the real-time applications.

It is found that real systems including Internet have the features of complex networks.A new holistic sight is given to the research of virus spreading on the complex Internet.Based on the previous work,a complex network model of Internet was constructed and the spread behavior on it was simulated.The similarity to the real spread data of Sasser shows that this model can reflect the features of the real Internet and the virus can be controlled through varying several parameters.

Semiconductor manufacturing process's complexity and randomness make it difficult to build determinate prediction model. A new method was presented which used RBF neural network to model this process. Manufacturing lines with various release control and scheduling policies were simulated by software simul8, and the sampling data got from the simulation model were used in the training and test of the prediction model. Results demonstrate that the model's output and the real samples output are basically identical and the model has great generalization ability. So the well-trained network can be used to forecast the state of the process rapidly and accurately, which lays foundation to prediction control and real time scheduling.

Auther proposed a brand new encryption method for video sequence, based on Chaos theory. This method adopted multilayer chaotic transformation,therefore,the key can be changed during theencryption process, and the security performance is greatly improved.Besides, this algorithm inherited the selective encrytion idea, it only processed the key messages in the video sequence, so encryption efficiency is enhanced remarkably to satisfy the requirements of realtime communication. Furthermore, through computer simulations, the security performance and encryption efficiency of this method was demonstrated.