Abstract: Provided is a magnetic material concentration measuring device including: a bobbin having an outer circumference around which an exciting coil, an output coil, and a further exciting coil are wound; an eccentric hole formed in the bobbin; a rotor that is rotatably fitted in the eccentric hole about an eccentric axis line; a first cutout part that forms a first flow passage on one end side in an eccentric axis line direction of the rotor; a second cutout part that forms a second flow passage whose angle is shifted in a rotor rotation direction with respect to the first cutout part, on another end side in the eccentric axis line direction of the rotor; and a communication passage that connects the first flow passage and the second flow passage.

Abstract: In feature value extraction processing step, feature values are extracted from time-series vibroacoustic data in equipment in operation. In machine learning diagnosis step, accumulated are feature values corresponding to normal equipment-operation-state and general measurement data on equipment. Probability distribution model related to correlation between general measurement data and feature values corresponding to normal equipment-operation-state and constructed through machine learning is fed with general-measurement data and feature values extracted in feature value extraction processing step to calculate degree of anomaly based on probability distribution model.

Abstract: A piston ring is provided with a thermal spray coating that contains tungsten carbide and chrome carbide as a hard phase, and contains nickel as a metallic binder phase, and is characterized in that the thermal spray coating is formed by the spraying of a thermal spray powder that has been produced by means of a granulation sintering method, and that contains hard particles in which the mean particle diameter of the tungsten carbide has been adjusted by means of a BET method to fall within a range of not less than 0.15 ?m and not more than 0.45 ?m.