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In recent years, computer viruses, Trojans, worms and hacker attacks are becoming increasingly popular. It has caused certain harm to the political, economic and social world, and poses a serious threat to the Internet and the national critical information system. The vast majority of the security threats are caused by the security vulnerabilities in the system or software, resulting in an endless stream of security incidents. The study of computer system security vulnerabilities and the construction of the vulnerability database is very important for improving the system security and reducing the occurrence of security incidents. The current status of the security vulnerability database is studied, the domestic and foreign famous vulnerability database is analyzed, a study of foreign security vulnerabilities development experience is made, as well as several ideas about the development of the domestic security vulnerability database is proposed.

As the economic environment of increasingly complex and changeful, many enterprises through forming a strategic alliance to solve the bottleneck problem in the development of enterprises. League member enterprises face various of risks, which is not only impact the stability of the league as a whole, also an important factor to consider when the alliance making profit distribution. So how to correctly evaluate the risk of the member enterprises is particularly important. This paper constructs the evaluation index system of risk—taking of the member enterprises, based on the analysis of strategic alliance risks. And adopt the coefficient of variation method to get a comprehensive risk of every enterprise. Finally combining with case analysis on the feasibility and rationality of the evaluation index system are verified.

The different mapping systems is analyzed in this paper, and as a way of acquiring elevation with high accuracy and effectiveness, laser altimeter can improve the capability of 3- dimensional earth observation of satellite optical remote sensing imagery. And using high accuracy elevation observation of space-borne laser altimeter as control points accords with the trend of satellite photogrammetric without ground control points. In this paper, the problems of satellite photogrammetric are firstly introduced, and then the method of space-borne laser altimeter supported aero triangulation is described, which can solve these problems due to the characteristics of laser altimeter. The bundle adjustment error equations are established according to the earth observation of satellite image and space-borne laser altimeter, as well as the relationship of their exterior orientation elements. Elevation observations supplied by laser altimeter can be used as elevation control points to improve the accuracy of aero triangulation and the positioning accuracy. Finally, the improvement of elevation accuracy is shown by simulation using aero triangulation experiment of satellite image and space-borne laser altimeter, which can be improved from 9m to 1.6m.