Functional electrical stimulation to re-learn how to execute impaired functions, instead of making the consumer dependent on neuroprostheses for the rest of her/his life. Neurons are electrically active cells. In neurons, information is coded and transmitted as a series of electrical impulses called action potentials, which represent a brief change in cell electric potential of approximately 80–90 mV. Nerve signals are frequency modulated; i.e. the number of action potentials that occur in a unit of time is proportional to the intensity of the transmitted signal. Typical action potential frequency is between 4 and 12 Hz. An electrical stimulation can artificially elicit this action
Signals, Crane and Subway, Charters Towers railway station the signal box, although electrical or hydraulic operation could be used for more distant signals. At night, lights were necessary, and kerosene lamps with movable coloured spectacles displayed different colours, including green (proceed), yellow (prepare to find next signal red), and red (stop). Later, electrical coloured lights were used. Smaller points indicator signals, which confirmed whether or not points had been switched, could be used for shunting within a railway yard, and the most common form was the rotating disk signal. These could also contain a kerosene lamp for night operation. To coordinate signals so that is impossible to give