An inventory with self-digestive engine is that the inventory system has several life inventory features such as internal cycle demand engine,stock self-recovering ability,and stock life-span degression etc.

A discrete system simulation model based on tool inventory theory with self-digestive engine was established in this paper,and recovering ability and life-span characteristics were given.

As OA systems of subsidiaries are independent and documents cannot be shared in different regions and different network environments within group enterprises, this paper utilizes data processing engine to realize email communication and document flow for examination and approval among various subsidiaries.