Variable energy constraints affect the implementations of neural networks on battery-operated embedded systems. This
paper describes a learning algorithm for randomization-based neural networks with hard-limit activation functions. The
approach adopts a novel cost function that balances accuracy and network complexity during training. From an energyspecific perspective, the new learning strategy allows to adjust, dynamically and in real time, the number of operations
during the network’s forward phase. The proposed learning scheme leads to efficient predictors supported by digital
architectures. The resulting digital architecture can switch to approximate computing at run time, in compliance with the
available energy budget. Experiments on 10 real-world prediction testbeds confirmed the effectiveness of the learning
scheme. Additional tests on limited-resource devices supported the implementation efficiency of the overall design
approac
