Molecular Solutions for the Minimum Edge Dominating Set Problem on DNA-based Supercomputing.

A fixing device and an image forming apparatus having such a device is constructed by an unfixed image forming unit to form an unfixed image onto a recording material in accordance with start of an image formation, a heater in which a heat generating material which generates a heat by an energization is provided on a substrate, the unfixed image formed by the unfixed image forming unit being heated and fixed onto the recording material by a heat from the heater, and a power supplying unit for supplying an electric power to the heater in a first mode with a first maximum power by the start of the image formation and, subsequently, for supplying an electric power to the heater in a second mode with a second maximum power. The first maximum power is smaller than the second maximum power. In both of the first and second modes, the powers are controlled so that the heater is set to a predetermined temperature. When a predetermined time elapses from the start of the energization by the start of the image formation or when a temperature sensor detects a predetermined temperature of the heater, the operating mode is changed from the first mode to the second mode.