Methods After analyzing the actual and subjunctive governance costs in environment,the solution measure of preventive capital wasused to quantify the ecological compensation in contributing region.

On the basis of the discussion on protective maturity of water and soil conservation forest (WSCF),investigations on Robinia pseudoacacia WSCF in Weibei Loess Plateau were made.

Protective maturity is the key in protective forest management.

Research progress on nursing cost of intensive care unit;

Study on nursing cost of cervical spondylotic operation during perioperation period in our hospital;

Forecast model of expressway maintenance cost;

Through analyzing the relation among the above three factors,the author establishes computation model about benefit of highway network,and obtains the law which the effect of the maintenance cost in different period on road network benefit by an example.

The decision support model for bridge component maintenance is developed on the basis of comparison of the annual average maintenance cost of bridge component among all selected maintenance schemes.

Currently, whole-life design for deteriorating bridges which is a kind of the newest design idea is proposed with the serious deteriorating bridges and the excessively high life cycle maintenance cost, which enables the bridge structures to find trade-off among life-cycle performance, serviceability and life cycle cost.

Cost models of maintenance cost,user cost and society cost were derived out.