【目的】针对极限学习机(ELM)神经网络在室内可见光定位(VLP)中收敛不稳定,易陷入局部最优状态,导致定位精度降低的问题,文章引入了麻雀搜索算法(SSA)确定ELM神经网络的初始权值和阈值,提出了SSA-ELM神经网络算法。【方法】首先,采集定...【目的】针对极限学习机(ELM)神经网络在室内可见光定位(VLP)中收敛不稳定,易陷入局部最优状态,导致定位精度降低的问题,文章引入了麻雀搜索算法(SSA)确定ELM神经网络的初始权值和阈值,提出了SSA-ELM神经网络算法。【方法】首先,采集定位区域内接收信号强度(RSS)与位置信息作为指纹数据;然后,训练SSA-ELM神经网络并得到预测模型,将测试集数据输入预测模型得到待测位置的定位结果;最后,设计了仿真实验和测试平台。【结果】仿真表明,在立体空间模型中0、0.3、0.6和0.9 m 4个接收高度,平均误差分别为1.73、1.86、2.18和3.47 cm,与反向传播(BP)、SSA-BP和ELM定位算法相比,SSA-ELM神经网络算法定位精度分别提高了83.55%、45.71%和26.26%,定位时间分别降低了36.48%、17.69%和6.61%。实验测试表明,文章所提SSA-ELM神经网络算法的平均定位误差为3.75 cm,比未优化的ELM神经网络定位精度提高了16.38%。【结论】SSA对ELM神经网络具有明显的优化作用,能够显著降低定位误差,减少定位时间。展开更多
As a new neural network model,extreme learning machine(ELM)has a good learning rate and generalization ability.However,ELM with a single hidden layer structure often fails to achieve good results when faced with large...As a new neural network model,extreme learning machine(ELM)has a good learning rate and generalization ability.However,ELM with a single hidden layer structure often fails to achieve good results when faced with large-scale multi-featured problems.To resolve this problem,we propose a multi-layer framework for the ELM learning algorithm to improve the model’s generalization ability.Moreover,noises or abnormal points often exist in practical applications,and they result in the inability to obtain clean training data.The generalization ability of the original ELM decreases under such circumstances.To address this issue,we add model bias and variance to the loss function so that the model gains the ability to minimize model bias and model variance,thus reducing the influence of noise signals.A new robust multi-layer algorithm called ML-RELM is proposed to enhance outlier robustness in complex datasets.Simulation results show that the method has high generalization ability and strong robustness to noise.展开更多
文摘【目的】针对极限学习机(ELM)神经网络在室内可见光定位(VLP)中收敛不稳定,易陷入局部最优状态,导致定位精度降低的问题,文章引入了麻雀搜索算法(SSA)确定ELM神经网络的初始权值和阈值,提出了SSA-ELM神经网络算法。【方法】首先,采集定位区域内接收信号强度(RSS)与位置信息作为指纹数据;然后,训练SSA-ELM神经网络并得到预测模型,将测试集数据输入预测模型得到待测位置的定位结果;最后,设计了仿真实验和测试平台。【结果】仿真表明,在立体空间模型中0、0.3、0.6和0.9 m 4个接收高度,平均误差分别为1.73、1.86、2.18和3.47 cm,与反向传播(BP)、SSA-BP和ELM定位算法相比,SSA-ELM神经网络算法定位精度分别提高了83.55%、45.71%和26.26%,定位时间分别降低了36.48%、17.69%和6.61%。实验测试表明,文章所提SSA-ELM神经网络算法的平均定位误差为3.75 cm,比未优化的ELM神经网络定位精度提高了16.38%。【结论】SSA对ELM神经网络具有明显的优化作用,能够显著降低定位误差,减少定位时间。
基金Project(21878081)supported by the National Natural Science Foundation of ChinaProject(222201917006)supported by the Fundamental Research Funds for the Central Universities,China。
文摘As a new neural network model,extreme learning machine(ELM)has a good learning rate and generalization ability.However,ELM with a single hidden layer structure often fails to achieve good results when faced with large-scale multi-featured problems.To resolve this problem,we propose a multi-layer framework for the ELM learning algorithm to improve the model’s generalization ability.Moreover,noises or abnormal points often exist in practical applications,and they result in the inability to obtain clean training data.The generalization ability of the original ELM decreases under such circumstances.To address this issue,we add model bias and variance to the loss function so that the model gains the ability to minimize model bias and model variance,thus reducing the influence of noise signals.A new robust multi-layer algorithm called ML-RELM is proposed to enhance outlier robustness in complex datasets.Simulation results show that the method has high generalization ability and strong robustness to noise.