A process for producing a ceramic structure, which comprises adding an organic assistant to a ceramic raw material mixture, kneading them to obtain a readily formable bullet, and extruding the readily formable bullet to obtain a ceramic structure, wherein the organic assistant is composed mainly of an organic compound giving a haze of 10 to 90% when made into a 5 weight % aqueous dispersion. Engaging members and first stopper portions are integrally formed with a first flange portion of the first divided housing unit. The dynamic-range compression processing is to compress a dynamic-range of density variation to be expressed on the reflex-type recording medium. The first component display, the second component display, and the beamsplitter are positioned such that the beamsplitter provides a composite image of the transmitted display area and the reflected display area. The conversion device functions in such a way that the gearshift lever is coupled with an axially displaceable and radially pivotable shift finger shaft. A repeater receives the signals from the command transmitter and in turn, in the presence of a valid ID, sends a command signal to the object actuating system, which in turn moves the object only if the ID from the repeater is valid.