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Limited by multiple factors, such as land use planning, landscape coordination and environmental standards, the ventilation conditions of the urban highway tunnels are insufficient, and therefore the joint control of ventilation and purification becomes a necessary solution. In this study, the effect of number, location of decentralized purification equipment, and the tunnel ventilation rate on pollution in the tunnel are studied using one-dimensional calculation. The results show that the arrangement of purification equipment can reduce the design ventilation rate to a certain extent. When purification equipment is arranged, the maximum NO2 concentration can be reduced by up to 30.9%, and the average NO2 concentration can be reduced by up to 18.2% compared with that without purification. The purification equipment arranged in the rear section of the tunnel is conducive to reducing the concentration of pollutants at the exit, while the arrangement in the middle section of the tunnel is conducive to reducing the average concentration of pollutants in the tunnel.

The influences of the slope composition on both sides of the variable slope point and the opening numbers of the exhaust vent on the smoke diffusion and the smoke and heat exhaust efficiency in V-shaped tunnel were investigated by the numerical method. The results showed that for the asymmetric V-shaped tunnel, increasing the number of exhaust vents on the large slope side can improve the smoke and heat exhaust efficiency, but control the smoke in a smaller rang is relatively difficult. The corresponding smoke exhaust vent opening strategy should be drawn up in accordance with the composition of the slope of the V-shaped tunnel and the goal of the smoke control system in practice.

Rural highway has a significant impact to build a moderately prosperous society in all aspects, and it is an important critical infrastructure to build harmonious society. Highway has its own economics attributes, and rural highway also has its own characteristics. This paper combines with rural highway characteristics to analyze the supply model and problems of rural highway. It summarizes several mixed supply models of rural highways.

Public expenditure efficiency plays an increasing important role in the process of establishment and perfection of public finance system. Corresponding indexes are selected to empirically analyze the efficiency of local government’s public expenditure, which turned out to be not high. This paper pointed out the reasons why the efficiency isn’t high, such as the disequilibrium of government’s routine power and financial power, offside and absence of governments, and proposed some relevant suggestions.