PURPOSE: To discover a quasi-optimum resolution within a practical range of time and memory by executing mission scheduling while calculating the time range in which scheduling is possible and deciding the scheduling time in a distribution or integration method.

CONSTITUTION: A possible scheduling time range calculation means 4 calculates the time range in which scheduling is possible. When it cannot calculate it, a scheduling fine adjustment means 5 moves the mission scheduling to calculate the possible scheduling time range. A scheduling time deciding means 6 calculates the optimum scheduling time corresponding to distribution or integration from the time range in which scheduling is possible and inquires the resource supply quantity when executed according the scheduling time. These operations are executed in terms of the next mission and the mission scheduling time is decided. Thus, the quasi-optimum resolution is discovered within a practical range of time and memory.