Abstract: In a power estimator, a power coefficient-calculating section acquires an average value of the number of signal changes per unit time in each circuit range to thereby calculate a power coefficient for each circuit range or calculate a power coefficient for each circuit range when the average value of the number of signal changes per unit time is equal to 1, a correction coefficient-calculating section calculates a ratio of an average value of the number of signal changes per unit time at signal lines included in the circuit range to an average value of the number of signal changes per unit time at observing points designated in the circuit range, as a correction coefficient, and a power value-calculating section calculates a power value for each circuit range based on the correction coefficient and the power coefficient calculated for each circuit range.

Abstract: In a power estimator, a power coefficient-calculating section acquires an average value of the number of signal changes per unit time in each circuit range to thereby calculate a power coefficient for each circuit range or calculate a power coefficient for each circuit range when the average value of the number of signal changes per unit time is equal to 1, a correction coefficient-calculating section calculates a ratio of an average value of the number of signal changes per unit time at signal lines included in the circuit range to an average value of the number of signal changes per unit time at observing points designated in the circuit range, as a correction coefficient, and a power value-calculating section calculates a power value for each circuit range based on the correction coefficient and the power coefficient calculated for each circuit range.

Abstract: A method for readily measuring each motor parameter with high precision, with an induction motor at rest, and an apparatus for controlling the induction motor using these motor parameters are provided. The induction motor is set to a single-phase feed state or a feed state equivalent to that state. First, a stator resistance is measured from a current value and a voltage value at the time when a direct current command is given. Then, the current command of a current having an appropriately high frequency and a known current differential value is given to find a rotor resistance and a leakage inductance from current values and voltage values at two different times and the previously obtained stator resistance value. Then, the current command of a sine wave current having an appropriately low frequency is given to find a mutual inductance using the current value and the voltage value at the time. These measured values are used for a slip frequency operation and a speed estimation operation.

Abstract: A method for making a key top of a push button is disclosed, in which a part of a light intercepting paint, which is the uppermost layer at each of displaying portions on the top surface of the key top, is removed so as to expose a displaying ink printed previously under the layer in accordance with the shape of the display portion.

Abstract: An extensible structure comprising five or more longerons which can be resiliently deformed like a coil, a plurality of batten members arranged at certain intervals in the axial direction of the longerons to connect the longerons to one another, and two chords diagonally stretched on a plane formed a four connected points where the two longerons with at least one longeron interposed between them are connected by the two batten members adjacent in the axial direction of the longerons.