Taking the two-grades tree-shaped river network of someplace in southern Jiangsu province as an example,based on the water quality simulation by using S-P water quality model,the water pollution controlling optimization model,in which the object function was to minimize the sum cost of sewage disposal and transferring water for dilution,was established in this paper.

A two-step optimal design method based on the integer coding genetic algorithm for tree-type pipe network is proposed.

An optimization model for tree-type pipe network,in which the minimal investment is taken as objective function,is established and genetic algorithm is used to solve the problem.

Chitosan dendrimer networks can be obtained by hydrolysis and condensation of methoxysilyl end groups in the methoxysilyl terminated butyrylchitosan.

It also proposes the pattern of tree-network structure of urban green space based on the advantage and flaw of tree-type structure and network-type structure.