Applying the theories of new institutional economics, microeconomics,combined with actual observation, this article focuses on the repast and tourist industry to bring forward the economic explanation of tip system.

Application of the least expenditure method to project selection;

In this way, the problem of optimizing approval for wagon requisition was transformed into solving minimum cost and maximum flow in a network.

This paper regards networks as geometry graphics by introduced the theory of plane geometry based on the theory of minimum cost,and the mathematics model is established.

We study uncapacitated version of the minimum cost flow problem of one-commodity and two-commodity with not only fixed cost but also variable cost, and give them each a polynomial algorithm.

This paper discusses the smallest cost problem on the undirection network,which has the upper limit of rate of flow,and sets up its mathematics model,and gives its relevant algorithm.

The bandwidth-delay-constrained least-cost multicast routing problem is known to be NP-complete,and the immune algorithm to solve the problem is proposed in the paper.