1. A neural network, wherein a portion of the neural network comprises: a first array having a first number of neurons, wherein the dendrite of each neuron of the first array is provided for receiving an input signal indicating that a measured parameter gets closer to a predetermined value assigned to said neuron; a second array having a second number of neurons, the dendrite of each neuron of the second array forming an excitatory STDP synapse with the axon of a plurality of neurons of the first array; and the dendrite of each neuron of the second array forming an excitatory STDP synapse with the axon of neighboring neurons of the second array.