A group global positioning system includes a plurality of positioning signal processing devices with a global positioning function and a plurality of radio signal processing devices corresponding to the positioning signal processing devices. More particularly, the invention comprises a multi-axis andor multi-field charged particle cancer therapy system. The interworking facility also maps the destination address incorporated in the origin frame to a corresponding destination address of a format compatible with the destination network to facilitate forwarding of the second frame to the destination. When the wireless terminal learns from the beacon that there are packets waiting, it communicates with the access point to retrieve them. A high-temperature, porous vent is provided adjacent the discharge end of the metal sprue to expel air from the sprue that would otherwise be trapped therein. The carbazole derivatives comprise two carbazole groups and alkyl group andor spiro group inserted between the carbazole group and aromatic group, which is represented by formula 1.