INFLUENCE OF SAMPLE DATA PREPROCESSING ON BP NEURAL NETWORK-BASED GPS ELEVATION FITTING
样本数据预处理对基于BP神经网络的GPS高程拟合的影响

The necessity of sample data preprocessing for BP neutral network-based GPS elevation fitting is analyzed,and three preprocessing methods are given,which are normalization,centralization and standardization.In order to obtain an optimal model,a data preprocessing layer is added in the network topology and then the three different methods are applied in training the neutral networks.Through the comparative analysis of the results derived with different preprocessing methods and with quadratic surface model,i...