The modeling of operating timing sequence of cigarette sorting system was established,including the modeling of supplementing cigarettes operation,sorting operation time of sorting machine of tower cigarettes and sorting machine of horizontal cigarettes.

By constructing a good limiting cognitive structure as the centre, the author has made a breakthrough in e "high threshold" of teaching management; the adoption of such measures as diversification teaching, guiding students by construction assignments and building studying communities has obviously lessened all kinds of difficulties in .