With the development of space technology and information technology,the application domain of space systems has become wider and wider,space security has gotten more attention of each country.

On basis of activity of "Without Accident" at Party member side held by Party branch of H_2SO_4 Manufacturer, the successful experiences of safety work are summarized to perfect safety management and promote enterprise development.

This paper introduces the functions of pre-shift meeting and post-shift meeting in the safety work of substation,and probes into how to hold well the pre-shift meeting and post-shift meeting.

This paper discusses on the necessity and the general target of the security work of university library,analyzes on several main links of the security work of university library,and expounds the importance of the security work of university library.

This paper briefly expounds the main contents of the security work o f university library, and in the light of the new situation of the security work , makes research on corresponding countermeasures and preventive measures, and d iscusses on the importance of the security work on the development of university library cause.

Workspace Analysis of a Laser Cutting Machine Tool Based on Delta Parallel Structure;

Workspace Analysis of Parallel Manipulator Based on Virtual Prototyping Technology;

Determination and Surface Reconstruction of the Workspace of BKX-I Variable-axis NC Machine Tool;