In such fields as road milling, mining and trenching it is often desirable to engage and degrade tough materials such as asphalt, concrete and rock. The set of space-charge control electrodes is located between a first terminal, such as a gate or a cathode, and a second terminal, such as a drain or an anode, of the device. The access data acquired form the network 601 and directed to the server 501 is judged by the firewall 401 in order to determine whether its data transfer is enabled or disabled, and the access data with its data transfer judged to be enabled is transferred to the server 501. The first and second legs of the serpentine flow cooling channels are located on the pressure side, and the third leg or channel is located on the suction side of the blade downstream from the gage point and where no further film cooling is preferred. In addition, the apparatus includes a clientserver open communications session manager, a client secure communication session manager, a clientserver secure communications session tracking database; and a data packet encryption and decryption engine. Since the CCD image sensor is sensitive to infrared light as well as to visible light, an image signal is outputted for the composite image according to the incident light from the optical filter.