An electronic apparatus comprises a housing containing a heat-generating component, and a cooling unit. A lateral opening connects the inlet with each passage beneath a removable plug closing the upper end of each passage, and valves are mounted in the housing each to close the passage beneath the lateral opening and thus beneath a ball on plug in the passage. The determination unit determines as to whether or not each pixel of the image data binarized by the binarization unit forms a peripheral portion of a pixel block. By opening the left side housing door, the inclined grip portion of the connecting support member comes out, permitting a servicing worker to hold on thereto helping him or her perform a cleaning job of a rear face portion of a cab in an efficient manner. The succession of human-perceptible stimuli may be harmonized, in which case, an association between the initiating device and the responding device is validated when the human-perceptible stimuli formed by the initiating device and the human-perceptible stimuli formed by the responding device are harmonized together.