In order to select more reasonable relay nodes for message transmission and improve the efficiency of message delivery in opportunistic networks, message forwarding utility was designed, a corresponding message copy forwarding algorithm was proposed. Firstly, based on the historical encounter information of nodes, the indirect encounter probability of nodes and the corresponding time-effectiveness were analyzed， then a time-effectiveness indicator was proposed to evaluate the encounter information value. Secondly, combined with the similarity of node motion, the problem of message repeated diffusion was analyzed, a deviation indicator of node movement was proposed to evaluate the possibility of message repeated diffusion. Simulation results show that compared with Epidemic, ProPHET, Maxprop, SAW (Spray And Wait) algorithms, the proposed algorithm has better performance in delivery success rate, overhead and delay.

Group formation control technologies are ofen used for the film formation scenes of a large number of characters in film and television works, but a lot of group formation technologies tend to focus on the free-moving individual characters without considering the overall control of the formation, which causes the scene picture a lack of beauty, integrity and organization. In order to solve these problems, a group formation control method based on Voronoi diagram was proposed. Firstly, the group formation was divided into Voronoi diagram spaces to create a formation grid containing all the agents. Then, a new group formation deformation algorithm was proposed, in which artificial potential energy field and relative speed obstacle method were used to reasonably avoid obstacles, and a spring system was combined to keep the formation as stable as possible in the deformation process. Finally, Lloyd algorithm was used to quickly restore the target formation. The experimental results show that, the proposed method can simulate the group formation transformation motion well, is suitable for various complex scenes, and has an aesthetic, overall and organized formation transformation effect.

Since the efficiency of retrieval and query of mass and high-speed space targets remains in a low level, a construction method of sphere grid index to the space targets based on the orbit restraint was proposed. The advantage that the orbit of space target is relatively stable in earth inertial coordinate system was used in the method to achieve the stabilized index to high-speed moving objects by maintaining the list of the space targets that pass through the sphere subdivision grid. On this basis, a region query application scheme was proposed. Firstly, the query time period was dispersed according to a particular step value. Secondly, the boundary coordinates of the query region in the inertial space were calculated and the staggered mesh was confirmed. Then the space targets in the grid were extracted and the spatial relationship between targets and the region was calculated and estimated. Finally, the whole time period was queried recursively and the space targets transit query analysis was accomplished. In the simulation experiment, the consumed time of the traditional method by calculating one by one has a linear positive correlation with the target number, but it has no relevance with the region size. One target costs 0.09 ms on average. By contrast, the time of the proposed method in the paper shows a linear decrease with the decline of area size. When the number of the region grids is less than 2750, the time efficiency is higher than that of the comparison method. Furthermore, it can maintain a fairly good accuracy. The experimental results show that the proposed method can improve the efficiency of the query in the actual region application effectively.

The blind signature is widely applied to the electronic voting system and electronic paying system, etc. While giving a blind signature, the signer does not know the content of the signed message. This paper analyzed the security of a new certificateless proxy blind signature scheme (WEI CHUN-YAN, CAI XIAO-QIU. New certificateless proxy blind signature scheme. Journal of Computer Applications, 2010,30(12):3341-3342) and found out the security loophole. The signer can link the signed message with the original message. Thus the scheme can not satisfy the security requirements of the blind signature scheme. To solve this problem, an improved scheme was proposed. The improved scheme eliminates the defect of the original one.

To enhance the performance of Shuffled Frog Leaping Algorithm (SFLA) in solving optimization problems，this paper proposed an improved shuffled frog leaping algorithm. By adding mutation operator to the original algorithm, the improved algorithm regulated the scale of mutation operator via fuzzy controller, made a dynamic adjustment of mutation operator in the searching range of solution space with different phase and candidate solution distribution of evolution process. The simulation results of four typical functions of optimization problems show that the proposed algorithm can attain above twice improvement on accuracy, convergent speed and success rate, and it demonstrates a better optimization capability especially in solving the high dimensional complex optimization problem, in comparison with the basic shuffled frog leaping algorithm and the known improved algorithm.