Research On Imporved Artificial Fish Swarm Algorithm And Its Application In City Flood Control Operation

In recent years,urban waterlogging disatsers have been occurred frequently in China,causing serious economic losses and even casualties.It has become a prominent problem that restricts the sustainable development of the national economy and threatens social public safety.Focused on the key technologies in urban flood control and drainage operation,this paper proposes Opposition-based Cauchy mutataion Artificial Fish Swarm Algorithm with Adaptive Step and develolps an urban waterlogging optimal operation system that integrates information collection,waterlogging simulation,and optimal operation.The main research contents and innovative achievements of the paper are summarized as follows:The paper analyzes the severe urban waterlogging situation and its causes in China,and explains the importance of forming an urban flood control system that combines storage,stagnation and drainage,and uses intelligent algorithms to scientifically and effectively optimize it.This paper introduces present domestic and international research progress from three aspects: rain flood model,urban drainage system optimal operation method,and urban drainage optimal operation system platform,which provides a research basis for the improved optimization algorithm,the establishment of flood control optimal opeartion model and the construction of urban flood control system platform in this paper.The paper introduces the Artificial Fish Swarm Algorithm(AFSA)and its four basic optimization behaviors.It adopts three improved strategies to solve the defects of AFSA,and proposes Opposition-based Cauchy mutataion Artificial Fish Swarm Algorithm with Adaptive Step(OCASAFSA).The test results of five commonly used test functions show that the algorithm is superior to AFSA in terms of optimization accuracy,convergence speed and search stability.A flood control operation model of the Tangxun Lake system including two sub-models of waterlogging simulation and flood control optimal operation was established.The waterlogging simulation model is used to simulate the evolution process of flood in the system.The flood control optimal operation model uses OCASAFSA to optimize the gate opening of the waterlogging simulation model,looking for the best combination of gate openings for the operation target.Taking the design frequency heavy rain as the input of flood control operation model,the calculation results show that: Tangxun Lake,Nanhu Lake and Qingling Lake can resist the design rainstorm of once every 10 years,Yehu Lake and Huangjia Lake can resist the design rainstorm of once every 20 years;compared to conventional operation,the sum of the accumulated water levels which exceeded the preflood control water level during the operation period of each lake,was reduced by 12.33 m in the case of optimal operation,a reduction of 6.3%,and the maximum operating water level of each lake was reduced by 0.048 m on average.It proves the importance of the urban flood control operation model for flood control project evaluation and flood control drainage regulation..Based on the urban flood control operation model and Web technology,a B/S architecture urban flood control operation system was built.The basic architecture,logical structure,technical architecture,development environment and database design of the system are expounded,and the main functions of the system were developed,which provide a basis for the assessment of the flood control capacity of the water system,and provide decision support for the urban flood control operation.