Matrix element calculation carried out efficiently without the overhead of communication between a host computer and processor elements even in parallel calculation utilizing a low-cost communication device and multiple processor elements having memories of a small capacity. More specifically, the bistable switch includes a substrate having at least one power source; a flexible sheet having a first distal end attached to the substrate; a bridge contact formed at a second and opposite distal end of the flexible sheet; and at least one heat activated element connected to a first surface of the flexible sheet and between the second distal end and the power source. In the formula, n represents a positive number of 1 to 10 as an average value. The cabin pressure control system may have manual and auto controls controlling separate motors on each outflow valve. The first conductive region is separated from the second conductive region by the passivation layer.