A technique is disclosed for generating a new contour andor a 3D surface such as a variational implicit surface from contour data. The interconnect substrate includes a third inductor and a fourth inductor. An output amplifying stage amplifies the pair of intermediate differential signals to provide a pair of output differential signals. On the other hand, when the spark ignition combustion is performed, a normal feedback control of air-fuel ratio activates a three-way catalyst to reduce HC, CO and NOx simultaneously. The objective start rpm of the starter is raised and the objective start rpm of the ISG is lowered as the engine temperature is lowered.