@Override
 public void handleLearningEvent(LearningEvent event) {
   BackPropagation bp = (BackPropagation) event.getSource();
   LOG.error("Current iteration: " + bp.getCurrentIteration());
   LOG.error("Error: " + bp.getTotalNetworkError());
   LOG.error("Calculation time: " + (System.currentTimeMillis() - start) / 1000.0);
   //   neuralNetwork.save(bp.getCurrentIteration() + "CNN_MNIST" + bp.getCurrentIteration() +
   // ".nnet");
   start = System.currentTimeMillis();
   //            NeuralNetworkEvaluationService.completeEvaluation(neuralNetwork, testSet);
 }