Abstract: Provided is a control device connected to a display panel including a controller configured to display images by driving the display panel according to data corresponding to image frames, and a memory connected to the controller. The controller is configured to select at least one of the image frames as a reference image frame, and update stress data corresponding to a partial area of the display panel in the memory based on one image data block selected from image data blocks of the reference image frame.

Abstract: A brake device for elevator, including a hollow box-shaped elevator car (1) for holding the passenger or luggage; block (5) having a pair of guide rails (6) for guiding upwards and downwards the elevator car (1); a plurality of racks (4) disposed at the block (5) along the lifting direction in vertical; at least one motor (2) tooth-engaged with at least one pinion (2a) at the racks (4), for lifting upwards and downwards the elevator car (1), clutch (12) for controlling power transmission to connect a driving shaft (19) to a driven shaft (20) when the pinions (11) engaged with the racks (4) are rotated at high speed due to elevator crash; hydraulic pump (15) for generating hydraulic pressure from power transmission through a plurality of transmission gears (13) when the clutch (12) delivers rotation; and a plurality of hydraulic cylinders (17) for braking the elevator by brake pad (18) in tight coupled with the guide rails (6) by hydraulic power from the hydraulic pump (15).