Parameters Inversion Of Niche Particle Swarm Algorithm With Basin Flood Routing Model

Problems of floods have been concerned for thousands of years, people try totake various methods to solve it. For example, we can calculate flow and velocity atdifferent time by the flood routing model, and it plays an important role in floodforecasting and control. The problem of the parameters inversing model is animportant step, which plays a key role in the application of the flood routing model.Particle swarm optimization is a member of swarm intelligence algorithms, it isa global optimization algorithm. The algorithm issimple and it has many goodoptimal performance and strong robustness. However, the particle swarm algorithmhas two major drawbacks: it’s easily stuck in local, and it converges slowly. Particleswarm algorithm has many shortcomings. So scholars put forward a lot of improvedalgorithms. We summarize the many previous methods. This article selects the nicheparticle swarm algorithm basing on fitness sharing. The algorithm combines fitnessvalues shared niche technology with the particle swarm algorithm.Firstly, we solve the problem of typical multi-modal optimized function withthis algorithm. We compare optimized results with the results of the particle swarmoptimization algorithm. We verify the efficience and superiority of the algorithm.And we discuss the convergence of the algorithm. Secondly, we apply algorithm topractical problems. We use the flood routing model of the existing analyticalsolutions to solve the value of parameter inversion, and the results show that themethod has high accuracy and fast convergence, and it is almost the same with thetrue value. Finally, we study a case when the noise level changes from5%to15%.From the experimental, inversion results of the parametersK and x are not verygood when the noise level is5%. Therefore, in order to improve the noise immunityof the proposed method, we try to combine the multi-scale approach with the nicheparticle swarm optimization to form a multi-scale niche particle swarm optimization.It is applied to parameter inversion in the flood routing model. The numerical resultsshow that results of single parameter inversion are highly accurate and almost thesame with the true values. However, the accuracy of dual-parameter inversion is notvery high, and it needs to be improved. The results of simulation demonstrate thefeasibility and the anti-disturbance of the algorithm. The algorithm has a high valueof practical application in the parameters inverse of the flood model, and it is expected to be used widely.