A plurality of pieces of process data are acquired from a semiconductor production apparatus while it is in operation, and then, a multivariate analysis model is created using at least a portion of the plurality of pieces of process data. In some embodiments, the SOI substrate has a handle wafer. The full close stopper locks the throttle lever when the throttle valve is fully closed. The computer program product also highlights a respective display control included in the selected tab, which corresponds to the possible reason why the deactivated display control is deactivated. This configuration is free from overflow and underflow of the receiving buffer due to difference in clocks between the transmitting and receiving ends, and prevents the occurrence of packet jitter so as to avoid voice sound breaks. Owing to this inclination, the gallium nitride based semiconductor epitaxially grown on the primary surface 32a of the gallium oxide support base has a flat surface.