School of Technology, Beijing Forestry University, Beijing, China.
National Agricultural Intelligent Equipment Technology Research Center, Beijing, China.
PLoS One. 2019 Sep 4;14(9):e0221729. doi: 10.1371/journal.pone.0221729. eCollection 2019.
Past research on the process of extinguishing a fire typically used a traditional linear water jet falling point model and the results ignored external factors, such as environmental conditions and the status of the fire engine, even though the water jet falling point location prediction was often associated with these parameters and showed a nonlinear relationship. This paper constructed a BP (Back Propagation) neural network model. The fire gun nozzle characteristics were included as model inputs, and the water discharge point coordinates were the model outputs; thus, the model could precisely predict the water discharge point with small error and high precision to determine an accurate firing position and allow for the timely adjustment of the spray gun. To improve the slow convergence and local optimality problems of the BP neural network (BPNN), this paper further used a genetic algorithm to optimize the BPNN (GA-BPNN). The BPNN can be used to optimize the weights in the network to train them for global optimization. A genetic algorithm was introduced into the neural network approach, and the water jet landing prediction model was further improved. The simulation results showed that the prediction accuracy of the GA-BP model was better than that of the BPNN alone. The established model can accurately predict the location of the water jet, making the prediction results more useful for firefighters.
过去关于灭火过程的研究通常采用传统的线性射流着落点模型,并且结果忽略了外部因素,例如环境条件和消防车的状态,尽管射流着落点位置的预测通常与这些参数相关,并表现出非线性关系。本文构建了一个 BP(反向传播)神经网络模型。将水枪喷嘴特性作为模型输入,将排水量点坐标作为模型输出,从而可以精确地预测排水量点,误差小,精度高,确定准确的射击位置,并及时调整喷枪。为了提高 BP 神经网络(BPNN)的收敛速度慢和局部最优性问题,本文进一步使用遗传算法对 BPNN(GA-BPNN)进行优化。BPNN 可以用于优化网络中的权重,以进行全局优化。引入遗传算法到神经网络方法中,进一步改进了射流着落预测模型。仿真结果表明,GA-BP 模型的预测精度优于单独的 BPNN。所建立的模型可以准确地预测射流的位置,使预测结果对消防员更有用。