A bonded abrasive grinding wheel is provided with a bonded abrasive disc including abrasive grain disposed within a bond matrix, and a mounting plate integrally fastened to the disc. The system operates by receiving a request at the database to perform an encryptiondecryption operation, wherein the encryptiondecryption operation is performed with the assistance of the external security module in a manner that is transparent to database applications. The transmitting section writes response information of the self node for the control information contained in the received control cell in an area corresponding to the self node in the control cell and transmits the control cell to a downstream node. The swingable body is coupled to the moving roller. The portable device is further adapted to receive the light output from an external light source for use with the fourth mode.