Fig. 1: Schematic diagram of UPENN and USRNN with transfer learning ability and the structural diagram of N-LEM with photoelectric equivalent transmission and UV suppression.

a A schematic diagram of pre-learning method and cross-regional hierarchical structure in biological brain. After pre-learning, the brain can process the unlearned content. b Schematic diagram of neural network for photoelectric parallel transmission with cross-layer transmission structure. c Structure diagram of N-LEM with negative UV photoconductive response and parallel output. d Schematic diagram of photoelectric equivalent transmission and UV negative photoconductive phenomenon of N-LEM.