Abstract: A tire state estimation system (10) is provided with a crack shape acquisition unit (240) for acquiring the shape of a crack on the outer surface of a tire, a crack information DB (230) for holding a correspondence relationship in which at least either degree of opening or deviation width of the crack based on the shape of the crack is associated with the depth of the crack, and a crack depth estimation unit (250) for estimating the depth of the crack based on the acquired crack shape and the correspondence relationship.

Abstract: In a system in which active and standby units, each used to control a VCXO on the basis of a reference signal from a GPS receiver to generate a high-precision clock, constitute a redundant arrangement, and a clock is output from the active unit, a clock generating circuit has an arrangement in which when the active unit cannot receive any reference signal from the GPS receiver for some reason, free-running operation is performed in the control state the VCXO assumed when the reference signal stopped in the internal circuit of the active unit, and switching to the standby unit is not immediately performed, and an arrangement in which when the standby unit can normally receive the reference signal from the GPS, the output clock from the active unit during free-running operation is monitored, and the unit that is to receive the reference signal is switched from the active unit to the standby unit at the timing at which no influence is exerted on the output clock when a phase difference larger than a predetermine

Abstract: An image forming apparatus includes a paper stacking section for stacking a plurality of paper sheets cut to a given size.