%0 Journal Article %T Contract Mechanism of Water Environment Regulation for Small and Medium Sized Enterprises Based on Optimal Control Theory %A Shuang Zhao %A Hongbin Gu %A Lianfang Xue %A Dongsheng Wang %A Bin Huang %J Journal of Water Resource and Protection %P 538-556 %@ 1945-3108 %D 2024 %I Scientific Research Publishing %R 10.4236/jwarp.2024.167030 %X The small and scattered enterprise pattern in the county economy has formed numerous sporadic pollution sources, hindering the centralized treatment of the water environment, increasing the cost and difficulty of treatment. How enterprises can make reasonable decisions on their water environment behavior based on the external environment and their own factors is of great significance for scientifically and effectively designing water environment regulation mechanisms. Based on optimal control theory, this study investigates the design of contractual mechanisms for water environmental regulation for small and medium-sized enterprises. The enterprise is regarded as an independent economic entity that can adopt optimal control strategies to maximize its own interests. Based on the participation of multiple subjects including the government, enterprises, and the public, an optimal control strategy model for enterprises under contractual water environmental regulation is constructed using optimal control theory, and a method for calculating the amount of unit pollutant penalties is derived. The water pollutant treatment cost data of a paper company is selected to conduct empirical numerical analysis on the model. The results show that the increase in the probability of government regulation and public participation, as well as the decrease in local government protection for enterprises, can achieve the same regulatory effect while reducing the number of administrative penalties per unit. Finally, the implementation process of contractual water environmental regulation for small and medium-sized enterprises is designed. %K Optimal Control Theory %K Small and Medium-Sized Enterprises %K Water Environment Regulation %K Contract Mechanism %U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=134787