(Network solution technology is to use a directed network graph to express the sequence and logical relationship of each work in a solution; then calculate the time parameters to find out the key routes and available maneuvering time in the solution; in accordance with certain optimization. policy, and continuously improve and optimize the plan arrangement, so that the plan can achieve the overall optimization; and in the implementation process of the plan, by checking, controlling and adjusting to ensure the realization of the plan policy on schedule)