A thin film transistor substrate having an increased aperture ratio and a simple configuration. By means of the detection and scanning of the clearance sensor and the bias sensor, the ink cartridge carrier actively controls the optimum printing clearance between the ink jet nozzle and the media. The local log repository stores the logs and is size constrained. A receiving unit discovers an emergency event alert service. First and second shutoff valves are enclosed in the same integral, unitary housing which encloses the check valves and, preferably, some or all of the relief valve. The shelf structure facilitates drying of the apparel and prevents soiling of floors, walls and the like.