18 results about "Pre synaptic" patented technology

The invention discloses a pulse neural network hardware accelerator and a data processing method, and the accelerator is characterized in that a low-power-consumption three-stage pipeline CPU module is used for receiving input data, scheduling an SNN network acceleration instruction, and sending the input data to an asynchronous edge SNN hardware accelerator module through a coprocessor interface; the asynchronous edge SNN hardware accelerator module comprises a pulse data encoding and decoding module, L neuromorphic kernels and an on-chip network, the pulse data encoding and decoding module encodes input data into a pulse form and sends the pulse form into the neuromorphic kernels, and the neuromorphic kernels are used for performing calculation based on the data in the pulse form; the network-on-chip is used for communication between the neuromorphic kernels, and the connection between neurons before and after synapses in the neuromorphic kernels is realized by adopting a synaptic cross array. According to the invention, the data processing acceleration performance can be greatly improved.

The invention discloses a pulse neural network error back propagation training method based on local synaptic plasticity, and the method comprises the steps: 1, building a pulse response model, taking a pulse sequence before and after synaptic neurons discharge as input, calculating a post-synaptic potential through a synaptic kernel function and weighted summation, and enabling the post-synaptic neurons to generate a new pulse as output; 2, simplifying the post-synaptic potential into two independent components by refining the pulse discharge time and approximately calculating the post-synaptic potential boundary value; 3, approximating a derivative between the post-synaptic potential and pulse counting by using pulse time dependent plasticity through a simplified post-synaptic potential calculation formula; and 4, combining local synaptic plasticity with a global optimization mechanism through a pulse time dependent plasticity approximate unknown derivative. According to the method, the advantages of local synaptic plasticity and a global optimization mechanism are fully utilized, the learning and adaptive capacity of the spiking neural network is enhanced, the method is closer to a biological nervous system, and the classification precision on training static and neuromorphic data sets is improved.

The invention discloses an adaptive gradient-based spiking neural network training method, which comprises the following steps of: firstly, constructing a to-be-trained spiking neural network adopting LIF model neurons, and inputting data set samples into the to-be-trained spiking neural network in batches; then obtaining pre-synaptic inputs of all neurons in each layer and membrane potentials of all neurons in each layer in the spiking neural network to be trained, associating the width of the proxy gradient with statistical characteristics of the membrane potentials through a correlation function, and adaptively adjusting the width of the proxy gradient in each layer; and finally, calculating cross entropy loss of an output layer of the pulse neural network and a sample label, performing gradient back propagation, and updating a synaptic weight. According to the method, the problem of gradient disappearance or mismatching caused by fixed proxy gradient function width is effectively relieved, the energy consumed by single reasoning of the network is less, and the trained network has excellent classification performance.

This invention relates to the field of neuromorphic computing technology and provides a method and system for dynamic adjustment of synaptic weights in real-time neurofeedback for neuromorphic chips. The method includes: capturing the pulse signals and timestamps emitted by presynaptic and postsynaptic neurons; calculating the time difference between the presynaptic and postsynaptic pulses; when the absolute value of the time difference is less than a preset time window threshold, querying a pulse timing dependency plasticity rule base based on the sign of the time difference to determine the corresponding synaptic weight adjustment type; generating corresponding voltage pulse parameters based on the adjustment type and the current conductance state of the target memristor synapse; and applying a write voltage pulse to the target memristor synapse according to the voltage pulse parameters to adjust its conductance value in situ in real time, thereby dynamically updating the synaptic weights. This invention solves the problems of poor dynamic environment adaptability, low energy efficiency, and high learning latency caused by traditional offline weight update mechanisms.

There is provided a neurosynaptic processing core with spike time dependent plasticity (STDP) learning for a spiking neural network, including: a spiking neuron block including a pre-synaptic block and a post-synaptic block; a synapse block communicatively coupled to the spiking neuron block; a STDP learning block communicatively coupled to the spiking neuron block and the synapse block, the STDP learning block including a pre-synaptic event accumulator including a pre-synaptic spike event memory block and a pre-synaptic spike parameter modifier; a post-synaptic event accumulator including a post-synaptic spike event memory block and a post-synaptic spike parameter modifier, a weight change accumulator, and a weight change parameter modifier; a learning error modulator; and a synaptic weight modifier configured to modify a synaptic weight parameter based on a weight change parameter and a learning error corresponding to the synaptic weight parameter. There is also provided a corresponding method of operating and a corresponding method of forming the neurosynaptic processing core.

A method (100) for distributed learning of a temporal neural network in a communication network. The method is performed by a first node of the communication network, the first node associated to a pre-synaptic neuron of the temporal neural network. The method comprises receiving (S101), from a second node of the communication system, the second node associated to a post-synaptic neuron of the temporal neural network, an indication that a hidden state of the post- synaptic neuron has changed. The method comprises transmitting (S102), to the second node, a pre-synaptic stimuli and receiving (S103), with a scheduled acknowledgement message associated to the transmitted pre-synaptic stimuli, a hidden state information related to the post-synaptic neuron. Further disclosed are related apparatuses, computer programs, and computer program products.

The invention discloses a neural retina synaptic device for artificial vision and a preparation method thereof. The neural retina synaptic device includes: a substrate; the electrode consists of a gate electrode, a source electrode and a drain electrode and is formed on the substrate; the channel layer is formed by a zero-dimensional quantum dot / two-dimensional material heterojunction thin film, has enhanced response to optical signals, is formed on the substrate, is used for connecting the source electrode and the drain electrode to form an electrical path, and is far away from the gate electrode; and the gate dielectric layer is made of an electrolyte gate dielectric material and is connected with the channel and the gate electrode to form a double-electrode layer. The gate electrode receives an electric signal to simulate a synaptic front end, the channel layer receives an optical signal to simulate a retinal cell light sensor, the source electrode, the drain electrode and the channel layer complete information collection, processing and storage by reading voltage, and the electric synaptic front end is adjusted to obtain positive and negative light current response. The method is used for constructing a sensing, storage and calculation integrated visual neuromorphic sensing system.

Spiking events in a spiking neural network may be processed via a memory system. A memory system may store data corresponding to a group of destination neurons. The memory system may, at each time interval of a SNN, pass through data corresponding to a group of pre-synaptic spike events from respective source neurons. The data corresponding to the group of pre-synaptic spike events may be subsequently stored in the memory system.

The application discloses a kind of video physiological signal dynamic extraction method and device, collect video and carry out face detection and posture correction to each frame video;The corrected face image is divided into micro-grid, and the brightness of each micro-grid is response-delay coding, and the pulse sequence of presynaptic pulse neuron is generated;Through membrane potential model and mutual inhibition between pulse neurons, competition is carried out and combined with connection weight, and the pulse emission time and pulse frequency of postsynaptic pulse neuron are obtained;According to the time difference between presynaptic and postsynaptic pulse neuron, dynamically adjust connection weight;After sorting and screening the pulse frequency of all postsynaptic neurons, it is mapped to the pulse sequence formed by corresponding micro-grid and weighted fusion, and the final pulse wave signal is generated;Finally, the physiological parameters of practitioner are obtained by calculating pulse wave signal, and the connection weight is adjusted by signal quality evaluation, and the strategy optimization of pulse wave signal extraction is realized continuously.

A method (100) for distributed learning of a temporal neural network in a communication network. The method is performed by a first node of the communication network, the first node associated to a pre-synaptic neuron of the temporal neural network. The method comprises receiving (S101), from a second node of the communication system, the second node associated to a post-synaptic neuron of the temporal neural network, an indication that a hidden state of the post- synaptic neuron has changed. The method comprises transmitting (S102), to the second node, a pre-synaptic stimuli and receiving (S103), with a scheduled acknowledgement message associated to the transmitted pre-synaptic stimuli, a hidden state information related to the post-synaptic neuron. Further disclosed are related apparatuses, computer programs, and computer program products.

The invention discloses a crop pest detection and early warning system based on a fruit fly perception neural network in the field of pest monitoring and early warning, the crop pest detection and early warning system comprises a pre-synaptic nervous system network and a post-synaptic nervous system network, the pre-synaptic nervous system network is used for processing video information, and the post-synaptic nervous system network is used for constructing an early warning monitoring model. The visual field information is processed based on biological inspiration of a fruit fly visual system network. The APDNNM visual neural network model is used for solving the technical problem of pest detection in intelligent video monitoring. According to the model, spike neuronal cells are constructed and synthesized on the basis of a response characteristic mechanism of feedforward neuronal cells and LPTC neurons of a fruit fly visual nervous system to sense pest information existing in crops, and early warning detection is achieved.

The invention discloses a synaptic plastic mechanism bionic circuit based on a memristor, and relates to the technical field of bionic circuits, the bionic circuit comprises a synaptic enhancement module, a synaptic suppression module, a steady-state window control module, a synaptic conductance updating module and a synaptic unit; the design method of the circuit comprises the following steps: firstly, determining the amplitude of a positive voltage pulse applied to the memristor, designing a synaptic conductance updating module and a synaptic enhancement and suppression module according to the amplitude, generating a pulse signal capable of controlling the memristor conductance, connecting the signal with the memristor synaptic through the synaptic conductance updating module, and generating a memristor synaptic signal; and if the curve can be fitted with a biological synaptic plastic mechanism, the process is ended, and otherwise, the circuit is redesigned. The bionic circuit provided by the invention has low requirements on neuron signals before and after memristive synapse, the fitting precision of the simulated synapse plastic mechanism is higher, the dynamic range of the learning rate is wider, and the pulse width and the steady-state window can be more accurately controlled by introducing the steady-state window control module.

The invention belongs to the technical field of bionic synaptic devices, and particularly discloses a three-terminal voltage gating synaptic device based on a nanofluid channel and a preparation method of the three-terminal voltage gating synaptic device based on the nanofluid channel, and the three-terminal voltage gating synaptic device based on the nanofluid channel comprises a nanochannel layer; the gate control electrode layer is connected with the nano channel layer and is used for applying a gate voltage pulse and simulating a presynaptic membrane; and the epoxy resin layer is coated outside the nano channel layer and the gate control electrode layer. According to the application, independent grid control is introduced, multiple functions of biological synapses can be highly simulated, a device closer to a biological neuron function is provided for neuromorphic calculation, a complex and intelligent calculation system can be constructed, in addition, super-long time-history plasticity is realized by utilizing cation-pi bond interaction, and the calculation efficiency is improved. The method has excellent performance in long-time-history enhancement and long-time-history suppression, and the stability and durability of nonvolatile information storage and processing are improved.

The invention discloses a construction method of a PD (Parkinson's disease) cell model, Bromoiodoacetamide (one of iodoacetamide) is used for the first time to act on the PD cell model construction of SH-SY5Y, and the invention finds that the stable PD cell model can be established when the action concentration of the Bromoiodoacetamide is 20-40 [mu] M and the action time is 48 h. According to the scheme, through unique compound design (double-target inhibition), cell pathology precise induction (presynaptic alpha-syn deposition) and a rapid modeling window (20-40 [mu] M * 48 h), the following problems are overcome: (1) animal model anatomical distortion-virtual high SNpc density / DAT gradient anomaly; (2) a traditional cell model is single in mechanism and only simulates mitochondrial damage; and (3) disjointing a pathological process and lacking progressive alpha-syn phosphorylation.

The invention discloses a variable retention time organic electrochemical transistor based on gate capacitance and application of the variable retention time organic electrochemical transistor in synapse simulation. The invention provides a method for simulating neuron behaviors based on an organic electrochemical transistor, which comprises the following steps of: taking a grid electrode of the organic electrochemical transistor as a presynaptic membrane, taking a channel as a postsynaptic membrane, and doping and de-doping ions in an electrolyte solution to the channel under the driving of double-pulse voltage of the grid electrode so as to simulate a neurotransmitter to realize information conduction; according to the method, the short-time synaptic plasticity is regulated and controlled by adjusting the size of the grid capacitance. The invention also provides a neuromorphic organic electrochemical transistor and a neuromorphic device for realizing the method. The neuromorphic organic electrochemical transistor provided by the invention has the characteristics of controllable plastic function and adjustable retention time, so that a foundation is laid for establishing a chemical response plastic device, and possibility is provided for realizing complex synaptic plastic function simulation by using the organic electrochemical transistor structure.

A skincare formulation for reducing facial expression lines via multi-modal reduction of ACh concentration and activity. The formulation includes a carrier base, an inhibitory neurotransmitter and a plurality of neuromodulating peptides configured to inhibit ACh concentration and activity at the epidermis as well as at the neuro-muscular junction. The inhibitory neurotransmitter is configured to reduce neuronal excitability. The plurality of neuromodulating peptides includes a first neuromodulating peptide configured to compete with SNAP-25 in the SNARE complex of the motor neuron at the presynaptic terminal, a second neuromodulating peptide configured to destabilize the SNARE complex at the presynaptic terminal, a third neuromodulating peptide configured to inhibit fusion of ACh vesicles in neuron plasma membrane, a fourth neuromodulating peptide configured to inhibit contraction of muscles via inhibition of transmitter-gated ion channel communication at the postsynaptic membrane, and a fifth neuromodulating peptide configured to block reception of ACh at the muscle cell, the postsynaptic membrane.

The present invention belongs to the technical field of microprocessors, and specifically discloses a lightweight on-chip learning method based on a simplified SDSP algorithm for training spiking neural networks, including: performing rate encoding on an input image to convert a static frame image into a spiking form, and regarding each pixel point as a presynaptic neuron; the output layer of the spiking neural network consists of leaky integrate-and-fire neurons, where each neuron is a postsynaptic neuron, and the presynaptic neurons and the postsynaptic neurons are connected in a fully connected manner. Among them, the spikes emitted by the presynaptic neurons are presynaptic spikes, and the spikes emitted by the postsynaptic neurons are postsynaptic spikes; during the training of the spiking neural network, the weights of each synapse are updated according to a simplified spike-driven synaptic plasticity weight update method based on the calcium concentration Ca of the postsynaptic neuron. The present invention also discloses a system and a processor based on this method.

A method for processing data based on a neural network including a first layer including axons and a second layer including neurons, includes receiving synaptic weights between the first layer and the second layer; generating presynaptic weights, a number of which is identical to a number of the axons, and postsynaptic weights, a number of which is identical to a number of the synaptic weights, from the synaptic weights; and storing the presynaptic weights and the postsynaptic weights in a synapse memory.