并列题名：Research on key technology of laser communication based on polarization shift keying Research on key technology of laser communication based on polarization shift keying 并列题名：Research on key technology of micro beveloid gear reducer 并列题名：Research on key technologies of watershed information perception and 3D intelligent management 并列题名：Research on key techniques of clustering and text categorization based on support vector machines 并列题名：Development technology of WebGIS application based on open source