Backpropagation Neural networks 21 Forecasting 10 Mean square error 9 Neural network model 8 Neural-networks 8 Back-propagation neural networks 7 article 7 Decision trees 5 Deep learning 5 Deep neural networks 5 E-learning 5 China 4 Errors 4 Particle swarm optimization (PSO) 4 Students 4 back propagation 4 Auto-regressive 3 Back Propagation 3 Complex nonlinear system 3 Inverse problems 3 Joints (anatomy) 3 Learn+ 3 Learning systems 3 Multilayer neural networks 3 Muscle 3 Network-based 3 Neural network 3 Nonlinear systems 3 Principal component analysis 3