Aiming at the optimization of servers' energy consumption in data center and the reasonable migration time of Virtual Machine (VM), a VM migration algorithm based on Dynamic Adjusting Threshold (DAT) was proposed. Firstly, the migration threshold was dynamically adjusted by analyzing the historical load data acquired from Physical Machine (PM), then the time for migrating VMs was decided by the delay trigger mechanism and the PM load trend prediction. The VM migration algorithm based on DAT was tested on datacenter platform in the laboratory. Experimental results indicate that compared with the static threshold method, the number of the shut down PMs of the proposed algorithm is larger, and the energy consumption of the data center is lower. The VM migration algorithm based on DAT can dynamically migrate VMs according to the variation of PM load, thus improving the utilization of resources and the efficiency of VM migration, reducing the energy consumption of the data center.

Fisheye lens break the limit on the view field of the ordinary camera, and develop a new path for computer vision research and application. In spite of its advantage in broader view and importance in application, fisheye image has its own distortion. A way to correct the distortion of the whole fisheye image was introduced. A method called equal arc length mapping in cylinder model based on the spherical perspective was proposed to solve the problem of distortion. The specific derivation of the algorithm was also provided. The obtained images prove the effectiveness of the proposed algorithm.

A novel decoding algorithm of turbo codes was proposed in this paper. Based on the MAX-Log-MAP algorithm, the novel algorithm not only used the segment linearity function but also took the statistic of the decoding data into account. Experimental results demonstrate that it performs better than the MAX-Log-MAP algorithm using traditional segment linearity function.