Abstract: An upstream integrated value is an integrated value of a difference obtained by subtracting an upstream gas temperature at a starting point in time of integration from the upstream gas temperature after starting of the internal combustion engine. A downstream integrated value is an integrated value of a difference obtained by subtracting a downstream gas temperature at the starting point in time of the integration from the downstream gas temperature after the starting of the internal combustion engine. An anomaly diagnosing process obtains an anomaly determination result indicating that the exhaust purification device is in a removed state when a deviation between the upstream integrated value and the downstream integrated value is smaller than a reference level. The determination threshold is higher than a dew point.

Abstract: In a composite material manufactured by connecting a sintered body to a surface of a metal substrate, the connection strength under a high temperature is increased, stress relaxation in the composite material is attained, and the strength, wear resistance and corrosion resistance are improved. The sintered body has a multilayer structure having layers with different compositions, i.e. compositions that vary or differ in a direction perpendicular to the connection surface, and the volume relation between the respective layers of the sintered body and the substrate is (substrate volume.times.0.2).gtoreq.(sintered body volume/number of layers), while the thickness of each layer is at least 0.2 mm and not more than 5 mm.

Abstract: A sintered body having diamond grains dispersed and held in a matrix of cemented carbide or cermet is obtained by direct resistance heating and pressurized sintering. The sintering is performed at a liquid phase generating temperature in a short time, so that the diamond grains are not directly bonded to each other. Thus, a superhard composite member that has excellent hardness and wear resistance can be obtained without employing an ultra high-pressure vessel.