Change my ANN models and improve the prediction

Today, I changed my ANN models a little to set training and testing data manually and record them. The prediction results are a little better than before.

Summary:

 The following is the comparison of predicting 6 parameters. The training part is a little better. 85% data (354) are used for training and 15% data (62) are used for testing.

The median value of R2 in training data is 0.7553. The median value of NRMSE is 0.1575.
The following are four examples of  t2 distribution with different R2. Also, there are R2 distribution and NRMSE distribution.

The median value of R2 in testing data is 0.7220. The median value of NRMSE is 0.1685.

I also change the ANN model for 64 bins and plot these distributions.
The median value of R2 in training data is 0.8445. The median value of NRMSE is 0.1311.

The median value of R2 in training data is 0.7662. The median value of NRMSE is 0.1512.

Next week, I will try to see if I can improve the prediction accuracy more and start to write the paper.