Disclosed herein is a method for comparing documents. In the method for driving the display device, by which images are displayed with the use of a plurality of frame periods, the display device is driven so that a voltage of 20 V or higher can be applied to a gate of a transistor, which is a driving element, for 1 millisecond or longer in a period, in which any one of scan lines is selected, in each frame period. Pellets with different material characteristics can be grouped together in a single thermal battery to produce a thermal battery with characteristics that are the average of the characteristics of the pellets used to manufacture the thermal battery. The method also comprises evaluating the power system component based on the estimated response. The engine controller calculates an upper limit of applicable power duty Dlimit based on the detected current value I1, the fixed duty D1 and the preset applicable current value Ilimit.