Techniques and mechanisms for providing access to a function with an inputoutput device. Image data is accessed, along with depth information for pixels of an image. Further, the catalyst can be used alone for catalyzing the steam gasification of organic compounds from biomass while limiting the amount of tar produced in the synthesized gases. The thermal insulating layer comprises a second memory material. A method for heating, reducing and melting a raw material mixture containing carbonaceous reducing agents and an iron oxide-contained substance to manufacture metallic iron, characterized in that a liquid fraction in a solid and liquid coexisting phase of produced slag containing a multi-component gangue is controlled to thereby accelerate melting of solid metallic iron produced. A subtractor is fed by the amplifier and the first photodiode.