A communication system interface between a baseband unit and a radio frequency unit is configured to advantageously use a common set of lines to carry both transmit and receive baseband analog signals between the baseband and RF unit, thereby enabling a relatively lower signal count and permitting loopback testing of elements within the baseband and the RF units. The throttle valve control apparatus of an internal combustion engine has a throttle opening degree sensor constituted by an non-contact sensor using hole elements. The computer system uses the indicating data to determine the interactive elements designated by the stroke before applying a command to at least one object using the designated interactive elements. As a result, variations of the frequency characteristics due to thermal load on the piezoelectric body 11 can be reduced, and this makes it possible to obtain an ultrasonic transducer with uniform characteristics, and measuring accuracy of an ultrasonic flowmeter using a pair of the ultrasonic transducer can be improved. Such method may be implemented to automatically establish the correct orientation and color balance of an image. By covering the enlarged inner diameter portion, unwanted material is prevented from accumulating at said portion and from interfering with the expansion of the next casing into said portion to form a monobore.