Design Considerations

(4th-February-2021)

• What transfer function should be used?

• How many inputs does the network need?

• How many hidden layers does the network need?

• How many hidden neurons per hidden layer?

• How many outputs should the network have?

• There is no standard methodology to determinate these values. Even there is some heuristic points, final values are determinate by a trial and error procedure.

• Time Delay NNs

• A recurrent neural network is one in which the outputs from the output layer are fed back to a set of input units. This is in contrast to feed-forward networks, where the outputs are connected only to the inputs of units in subsequent layers.

• Neural networks of this kind are able to store information about time, and therefore they are particularly suitable for forecasting and control applications: they have been used with considerable success for predicting several types of time series.