Based on the principles of micro-economics,focusing on categorizing types of toll at the goal of toll,researching on the highway toll-rates determining models under the toll-rates of crowd levy,repayable levy,and for-profit levy,comparing and analyzing quantitatively on a variety of theories of highway tolls,it provides theoretical basis for solving urban road construction and tolls.

Selection of air Conditioning heat and cold sources of a hospital in Shijiazhuang, based on circumstances of the project, provides four heat and cold source schemes, comparatively analyses the initial investment, annual operating cost, energy efficiency and environment effect.

Makes an economic and technical comparison pf three plans pf air cpnditipningheat/cold source: centrifugal chiller+boiler, direct fired LiBr absorption chiller, heat pump, andconcludes that the plan of centrifugal chiller+boiler is the best because of its initialinvestment, annual operating cost, energy consumption and enviroment effect, etc.