132 results about "Electrode impedance" patented technology

The invention belongs to the field of biomedical engineering, and particularly relates to a puncture operation tissue recognition system based on bioelectrical impedance, which comprises a dual-electrode impedance needle used for collecting electric signal data in real time; the feedback display equipment is internally integrated with a trained random forest model and is used for processing the electric signal data according to the trained random forest model to obtain a classification result; the multi-frequency bioelectrical impedance analyzer is used for displaying the real-time acquired waveform and displaying the classification result of the random forest model at the same time; the dual-electrode impedance needle comprises a needle tube structure and an electrode structure located at the head of the needle tube structure. According to the invention, electric signals of different tissues are effectively obtained, and measurement errors and signal interference are reduced.

The invention discloses an electroencephalogram sensing electrode and a using method thereof.The electroencephalogram sensing electrode comprises a shell assembly, the shell assembly comprises a shell, a base and a top cover, the shell and the base are connected to form a slow-release probe containing cavity, the shell and the top cover are connected to form a liquid storage cavity, and a fluid valve, a slow-release material, a capillary hole plug, a rapid flow hole and a slow flow hole are arranged in the shell assembly; a semi-dry electrode is made by injecting conductive liquid or a wet electrode is made by injecting conductive paste, and through a fluid valve, a slow-release material, a capillary hole plug, a quick flow hole and a slow flow hole, the electrode can quickly supply liquid to the position between the electrode and the scalp to reduce resistance and slowly supply liquid to reduce resistance, and the electrode-scalp interface impedance can be quickly reduced and can be balanced and stabilized for a long time. The electrode has the advantages that the electrode can be used as a semi-dry electrode by injecting conductive liquid, can also be used as a wet electrode by injecting conductive paste, and has the functions of storing the conductive liquid for a long time without releasing the conductive liquid when the electrode is idle and supplying the conductive liquid in two modes of fast and slow to reduce scalp-electrode impedance when a user wears the electrode to acquire signals.

The invention relates to the technical field of electroencephalogram signal processing, and provides a brain-computer AI glasses electroencephalogram signal multi-dimensional quality dynamic detection method, which comprises the following steps: preprocessing collected electroencephalogram signals; performing task frequency band component analysis on the channel signals subjected to the matrix rank analysis, and calculating a power proportion of a target frequency band; performing maximum gradient analysis on the channel signal, and calculating the maximum gradient value of the channel signal; performing root-mean-square analysis on the channel signal, and calculating a root-mean-square value of the channel signal; performing fluctuation amplitude analysis on the channel signal, and calculating a peak-to-peak value of the channel signal; performing brain hemisphere symmetry analysis on the left and right homologous channel signals, calculating the correlation and mean square error of the channel signals, and setting a dynamic threshold according to the frequency band of the channel signals; obtaining an electrode impedance value, and mapping the electrode impedance value into an impedance score through a preset exponential attenuation function; the final quality score of the channel is obtained, and dynamic detection and real-time score updating of the electroencephalogram signal quality are achieved.

An exemplary wireless soft scalp electronic system and method are disclosed that can actuate commands for a brain-machine interface (BMI) or brain-computer-interface (BCI) by performing real-time, continuous classification, e.g., via a trained neural network, of motor imagery (MI) brain signals or of steady-state visually evoked potential (SSVEP) signals. In some embodiments, the exemplary system is configured as a low-profile, portable system that includes microneedle electrodes that can acquire EEG signals for a brain-machine interface controller. The microneedle electrodes may be configured as soft imperceptible gel-less epidermis-penetrating microneedle electrodes that can provide improved contact surface area and reduced electrode impedance density, e.g., to enhance EEG signals and the signal classification accuracy. The microneedle electrodes can be further integrated with soft electronics that can be mounted locally in proximity to the electrodes to reduce obtrusive wiring and improve signal acquisition quality.

The invention relates to the technical field of medical beauty medical instruments, and particularly discloses a radio frequency microneedle treatment device and a radio frequency energy control method, the radio frequency microneedle treatment device comprises a control module, an impedance detection module, a switch switching circuit and a microneedle array; the microneedle array comprises a plurality of microneedle electrodes, the microneedle array is divided into a plurality of positive electrode areas and a plurality of negative electrode areas, and each positive electrode area and each negative electrode area comprise at least one microneedle electrode; the impedance detection module is electrically connected with the switch switching circuit, the switch switching circuit is electrically connected with each microneedle electrode, and the impedance detection module is used for detecting impedance values of treatment area tissues corresponding to the positive electrode area and the negative electrode area; and the control module is electrically connected with the impedance detection module, sends an impedance detection signal to the impedance detection module, analyzes an impedance value distribution diagram of treatment area tissues corresponding to the microneedle array according to an impedance value detected by the impedance detection module, and selects a proper positive electrode area to be conducted with a proper negative electrode area according to the impedance value distribution diagram.

The invention discloses a flexible multi-channel multi-layer electrode, a preparation method and an electromyographic signal collector. The preparation method of the flexible multi-channel multi-layer electrode comprises the following steps: etching a silicon wafer, and cleaning the silicon wafer; preparing an AgNW / NG solution as a conductive material, and preparing an elastic substrate by adopting SEBS powder; a signal acquisition layer is prepared from a silicon wafer, a conductive material and SEBS powder, a wire shielding layer is prepared from the silicon wafer and the SEBS powder, and a packaging layer and an interference signal shielding layer are prepared from the silicon wafer, the conductive material and the SEBS powder; the packaging layer, the interference signal shielding layer, the signal acquisition layer and the wire shielding layer are fixedly assembled in sequence from top to bottom, and are connected with the flexible printed circuit board through the signal acquisition layer. The invention aims to solve the problems of high electrode impedance value, low signal-to-noise ratio and poor stretchability of a multi-channel electrode.

An exemplary wireless soft scalp electronic system and method are disclosed that can actuate commands for a brain-machine interface (BMI) or brain-computer-interface (BCI) by performing real-time, continuous classification. e.g., via a trained neural network, of motor imagery (MI) brain signals or of steady-state visually evoked potential (SSVEP) signals. In some embodiments, the exemplary system is configured as a low-profile, portable system that includes microneedle electrodes that can acquire EEG signals for a brain-machine interface controller. The microneedle electrodes may be configured as soft imperceptible gel-less epidermis-penetrating microneedle electrodes that can provide improved contact surface area and reduced electrode impedance density, e.g., to enhance EEG signals and the signal classification accuracy. The microneedle electrodes can be further integrated with soft electronics that can be mounted locally in proximity to the electrodes to reduce obtrusive wiring and improve signal acquisition quality.

The invention discloses a wafer cleaning liquid concentration dynamic monitoring system, and belongs to the technical field of semiconductor manufacturing. Aiming at the problems of large single parameter measurement error, poor equipment adaptability and frequent maintenance in the prior art, the invention provides a multi-physics field fusion detection scheme: acquiring ion concentration characteristics through a multi-frequency conductivity detection module (0.1 kHz to 10MHz), eliminating environmental interference in combination with a temperature-viscosity joint compensation module, and calculating the concentration of the ion in the multi-frequency conductivity detection module. An optical refractive index auxiliary verification module is used to realize cross verification, and a CNN-LSTM fusion model optimized by transfer learning is used to improve cross-device prediction precision. According to the innovativeness of the system, an anti-corrosion annular electrode array (titanium alloy iridium-plated) supports dynamic distance adjustment and pulse self-cleaning, an ultrasonic defoaming unit (1-3 MHz frequency self-adaption) restrains bubble interference, and a self-calibration module triggers online maintenance based on the conditions of the electrode impedance change rate (larger than or equal to 5%), temperature fluctuation and the like. Experiments show that the concentration measurement precision is improved to + / -0.5%, the HF / O3 rate ratio is controlled to be (1: 2.5 + / -0.3), the number of residual particles on the surface of the wafer is smaller than or equal to 5 per square inch, the service life of the electrode is prolonged to 8 months, and the yield is improved by 0.6%. The method is suitable for a wafer production line of 12 inches and above, and has the advantages of high precision, strong anti-interference and low maintenance cost.

The invention relates to the technical field of electromyographic signal analysis and processing, in particular to a low-delay electromyographic signal processing method based on multi-channel fusion, which comprises the following steps of: acquiring full-band electromyographic signals by using a surface electrode array, and screening channels by adopting a mode of combining a Pearson's correlation coefficient and mutual information; the method comprises the following steps: setting dual thresholds, combining signal strength and electrode impedance detection, then performing 20-500Hz Butterworth band-pass filtering, Z-Score standardization and normalization processing on screened signals to improve the signal quality, optimizing sliding window parameters through the Parseval theorem and a dynamic time warping algorithm, balancing the real-time performance and the feature extraction effect, and improving the accuracy and the accuracy of feature extraction. And finally, time domain, frequency domain and time-frequency domain multidimensional features are extracted in each time window, and feature vectors are generated through principal component analysis and linear discriminant analysis fusion and dimension reduction. The invention aims to solve the problems of poor real-time performance and low feature identification degree of the existing electromyographic signal processing method.

The invention provides a negative electrode material, a preparation method thereof and a secondary battery, and particularly relates to the technical field of secondary batteries. The preparation method comprises the following steps: dispersing graphite and transition metal salt into a dispersing agent, stirring and compounding, and drying to obtain a precursor; and placing the precursor in a furnace, and introducing water vapor into the furnace to carry out an etching reaction so as to prepare the porous graphite. Due to the existence of the pore channels, lithium ions can be quickly diffused into the graphite particles through the pore channels, and when the graphite particles are used as a negative electrode material in a secondary battery, the negative electrode impedance can be reduced, and the low-temperature performance of the secondary battery is improved.

The invention relates to the technical field of solid fuel cells, and discloses a porous gradient anode supported solid fuel cell impedance optimization method which is applied to a system comprising a plurality of porous gradient anode impedance sensors and an optimization controller. The method comprises the steps that a sensor collects voltage and current data to generate an impedance state data set; the optimization controller constructs a regional impedance state matrix, extracts features through processing, performs impedance distribution prediction in combination with a potential gradient and the like, outputs spatial and temporal distribution features through an impedance optimization model, and updates a data set; and dynamically optimizing regional electrode parameters according to the distribution characteristics, including voltage adjustment, current aggregation, resistance distribution and other operations. According to the method, through multi-sensor distributed acquisition, multi-dimensional feature analysis and dynamic modeling, accurate prediction and parameter dynamic regulation and control of electrode impedance spatial and temporal distribution are realized, the performance and stability of the solid fuel cell are improved, and the method is suitable for the field of solid fuel cell management.

The invention provides a power divider, which comprises a ceramic substrate, a magnetic core, an impedance capacitor and an isolation resistor, and is characterized in that an input end electrode, a first output end electrode, a second output end electrode and a grounding end electrode are arranged on the outer surface of the ceramic substrate; the magnetic core is arranged on the outer surface of one side of the ceramic base body in the thickness direction, the magnetic core is in a square ring shape, a power distribution winding is wound on the magnetic core, and the power distribution winding is configured to distribute an input signal of the input end electrode to the first output end electrode and the second output end electrode; the impedance capacitor is arranged on the outer surface of the ceramic substrate, one end of the impedance capacitor is connected with the input end electrode, and the other end is connected with the grounding end electrode; the isolation resistor is arranged on the outer surface of the ceramic substrate, and the isolation resistor is connected between the first output end electrode and the second output end electrode. The power divider can achieve the purposes of small size, wide frequency band and high reliability.

The invention belongs to the technical field of batteries, and discloses a composite negative electrode material, a negative electrode, a preparation method of the negative electrode, a battery and electric equipment. The composite negative electrode material comprises a negative electrode active material, a conductive agent and a prefabricated film; the surfaces of the negative electrode active material particles are coated with the prefabricated film, and the conductive agent is dispersed in the prefabricated film; the material of the prefabricated film comprises a polymer material. In the composite negative electrode material provided by the invention, the surfaces of the negative electrode active material and the conductive agent are simultaneously coated with the prefabricated film, so that the electron transmission of the negative electrode active material and the conductive agent is improved, the electrode impedance is reduced, and the electrochemical performance of the battery is improved.

The invention provides an electrode impedance test system for physical therapy. The electrode impedance test system comprises a microcontroller, a D / A conversion circuit, a power amplification circuit, a voltage detection circuit, a current detection circuit and a boosting transformer circuit. The microcontroller generates a square wave signal, the square wave signal is converted into a sinusoidal signal through the D / A conversion circuit, and the sinusoidal signal is amplified through the power amplification circuit. The boosting transformer transmits the amplified sinusoidal signal to the electrode slice, and the secondary side of the boosting transformer is connected with the voltage and current sampling circuit and is used for collecting a differential signal. According to the system, the electrode impedance of the electrode plates is detected through voltage and current sampling of the pair of electrode plates, common-mode interference and signal distortion are eliminated through the differential signal amplification circuit and the full-wave precision rectification circuit, and high-precision acquisition and detection of signals are ensured. The detected and rectified signals are converted into digital signals through the A / D conversion circuit, and the digital signals are input into the signal input end of the microcontroller.

The invention provides an early warning system and method for a radial artery compression hemostat based on multiple sensors, and belongs to the technical field of complication early warning. The method comprises the steps that S1, multiple types of physiological signals of a radial artery compression area are synchronously collected and subjected to digital processing; s2, discrete wavelet transform is carried out on the proximal end temperature and the telecentric end temperature; performing time domain analysis on the pulse signal, and extracting to obtain pulse amplitude; s3, constructing a temperature distribution model of the compression area based on the temperature difference signal; s4, the resistivity distribution of the compression area is reconstructed through the electrode impedance signal, and the errhysis position is positioned; s5, calculating a pressure change rate based on the pressure digital signal; calculating a pulse amplitude attenuation rate based on the pulse amplitude; and fusing the pressure change rate, the temperature gradient vector, the pulse amplitude attenuation rate and the errhysis index through a weighted summation formula to obtain a comprehensive risk value. According to the invention, through multiple types of sensors, the complication related parameter coverage rate is improved, and the complication early warning timeliness and accuracy are improved.

The invention belongs to the technical field of electrochemical biosensors, and particularly relates to an electrochemical biosensor based on probe strand displacement reaction. According to the sensor, a capture probe is fixed in a nuclear track membrane and is specifically combined with a detection probe, and when target nucleic acid exists, on the basis of the Toehold mediated strand displacement reaction principle, the target nucleic acid replaces the detection probe, and electrode impedance change is triggered to achieve detection. Particularly, reversible replacement between the target nucleic acid and the detection probe is realized by designing double Toehold structural domains. The electrochemical biosensor disclosed by the invention is simple, convenient, rapid and high in specificity, and a new thought is provided for constructing a high-sensitivity and reusable electrochemical biosensing platform.

The invention provides a high-capacity silicon-carbon composite negative electrode material and a preparation method thereof, and relates to the technical field of battery materials, the high-capacity silicon-carbon composite negative electrode material comprises the following components by mass: 20-50 parts of silicon-based particles, 3-8 parts of an interface modification layer, and 45-75 parts of a carbon matrix; the silicon-based particles are nano silicon; the interface modification layer is oxide or nitride and coats the surfaces of the silicon-based particles; the carbon substrate is prepared from 20 to 40 parts of graphite, 15 to 25 parts of amorphous carbon and 5 to 10 parts of carbon nanotubes; through the three-layer structure of the silicon-based particles, the interface modification layer and the carbon substrate, the cooperation of high capacity and high stability is realized, and the nano silicon-based particles give full play to the advantage of high capacity, so that the first discharge specific capacity of the material is higher; the interface modification layer reduces interface impedance of silicon and carbon and inhibits side reaction of silicon and electrolyte; the three-dimensional network of the carbon matrix not only reduces the electrode impedance, but also provides buffering for silicon volume expansion, and is obviously superior to the traditional graphite and the existing silicon-carbon negative electrode.

The invention relates to a method and a device for recommending electrode stimulation frequency. The electrodes are at least one selected from a plurality of electrodes implanted into a human body for electrical stimulation, the method comprising: obtaining impedance of each of the electrodes at different frequencies; calculating the standard deviation and the average value of the impedance of the electrode under each frequency; the health degree of each electrode at different frequencies is evaluated according to the proportional relation between the value of the impedance deviation average value and the standard deviation; the number of the electrodes with the optimal health degree under each frequency is calculated; and determining the frequency corresponding to the maximum number as the recommended frequency. The electrical conductivity of the electrode is represented by the electrode impedance, and the stimulation frequency of the electrode can be recommended to medical personnel by analyzing the measured electrode impedance under different frequencies, so that the problem that the current stimulation frequency of the electrode is inappropriate due to the change of the electrical conductivity of the electrode is solved.

The invention provides an optogenetics device which sequentially comprises a flexible substrate, a MicroLED layer, a shielding layer, a transparent electrode layer and a top insulating layer from bottom to top, the MicroLED layer comprises a MicroLED chip, the transparent electrode layer comprises a transparent electrode, a modification layer is arranged on the surface of the transparent electrode to reduce electrode impedance, the position of the transparent electrode right faces the MicroLED chip, and the shielding layer is arranged on the top insulating layer. The shielding layer comprises a transparent shielding area between the transparent electrode and the MicroLED chip, and the top insulating layer exposes the transparent electrode.

The invention provides a touch module, a touch screen and electronic equipment, the touch module comprises a plurality of touch units, each touch unit comprises a first electrode and a second electrode, each first electrode comprises a plurality of first sub-electrodes and a plurality of first connecting parts, each first sub-electrode extends along a first direction, the plurality of first sub-electrodes are arranged along a second direction, the first connecting parts are connected with the first sub-electrodes, and the second connecting parts are connected with the first sub-electrodes. Each first connecting part is connected with two adjacent first sub-electrodes, so that the plurality of first sub-electrodes are continuously conducted along the second direction; the second electrode and the first electrode are arranged in an insulated mode, the first electrode comprises a plurality of second sub-electrodes, the second sub-electrodes extend in the first direction, each second sub-electrode is arranged between every two adjacent first sub-electrodes, and each second sub-electrode is continuously conducted in the first direction. According to the touch unit, the electrode impedance can be reduced, the signal ratio can be increased, each touch unit can form a plurality of capacitive nodes, touch signals are enhanced, and the touch performance of a touch screen is improved.

The invention discloses a fatigue driving intervention method and system based on head electric pulse stimulation, and relates to the technical field of fatigue driving intervention, and the method comprises the steps: collecting the scalp micro-motion frequency and scalp-electrode impedance change of a driver through a head-mounted sensing device, and obtaining an original physiological state signal; calculating a current fatigue index according to the original physiological state signal, wherein the reduction of scalp micro-motion frequency and the increase of impedance fluctuation amplitude respectively correspond to the increase of fatigue degree and the aggravation of attention distraction; continuously comparing the fatigue index with a dynamically adjusted physiological threshold, and when the fatigue index exceeds the physiological threshold and maintains a preset duration, generating a first intervention triggering condition; and whether a second intervention triggering condition or a third intervention triggering condition is generated or not is judged by combining an intervention mode preset by a user, the continuous running time of the vehicle and a manual triggering instruction, and an intervention enabling signal is output based on the logic relation of the first intervention triggering condition, the second intervention triggering condition and the third intervention triggering condition.

This invention discloses a flexible multichannel multilayer electrode, its fabrication method, and an electromyography (EMG) signal acquisition device. The fabrication method of the flexible multichannel multilayer electrode includes the following steps: etching and cleaning a silicon wafer; preparing an AgNW / NG solution as a conductive material and using SEBS powder to prepare an elastic substrate; fabricating a signal acquisition layer using the silicon wafer, conductive material, and SEBS powder; fabricating a wire shielding layer using the silicon wafer and SEBS powder; and fabricating an encapsulation layer and an interference signal shielding layer using the silicon wafer, conductive material, and SEBS powder; assembling the encapsulation layer, interference signal shielding layer, signal acquisition layer, and wire shielding layer sequentially from top to bottom, and connecting the signal acquisition layer to a flexible printed circuit board. This invention aims to solve the problems of high electrode impedance, low signal-to-noise ratio, and poor tensile strength of multichannel electrodes.

The invention discloses an integrated impedance measurement system adaptive to a biological signal acquisition front end. The integrated impedance measurement system comprises a sine wave current generator, a band-pass filter, an amplifier module BPFA, a multiplexer and an analog-to-digital converter ADC which are communicated in sequence, the sine wave current generator is used for generating low-amplitude alternating current for measuring tissue-electrode impedance, and the alternating current acts on a measured electrode to generate corresponding alternating voltage; the band-pass filter and amplifier module BPFA is used for amplifying and filtering the AC voltage; an analog-to-digital converter (ADC) receives the amplified and filtered alternating voltage through a multiplexer to perform digital signal conversion, and tissue-electrode impedance measurement of the measured electrode acting on the tissue is completed; according to the invention, the amplitude of the AC voltage is controlled to accurately adapt to the + / -5mV input range of the existing acquisition front end, and the amplification and filtering modules are directly multiplexed to complete impedance signal processing without additionally configuring a special analog front end for impedance measurement, so that the integration level and the stability of a chip are improved.

The invention relates to an electroencephalogram signal preprocessing method and a related device thereof.The method comprises the steps that initial electroencephalogram signals collected by a multi-channel electrode array and at least one kind of auxiliary data collected synchronously with the initial electroencephalogram signals are obtained, and the auxiliary data comprise electrode impedance values and / or physiological state data; wherein the resistance reactance value indicates an electrode impedance value corresponding to the acquisition channel associated with the initial electroencephalogram signal, and the physiological data at least comprises motion posture data and / or physiological index data; performing multiple filtering processing on the initial electroencephalogram signal to obtain a filtered electroencephalogram signal; inputting the filtered electroencephalogram signals and at least one kind of auxiliary data into a signal restoration model, and optimizing the candidate electroencephalogram signals to obtain optimized target electroencephalogram signals. According to the scheme, the electroencephalogram signals can be preprocessed by dynamically adjusting the filtering parameters and utilizing the impedance value and the auxiliary data, and the quality of the electroencephalogram signals is improved.

The invention provides a bio-electricity signal and electrode impedance acquisition system and method, and relates to the technical field of bio-electricity signal acquisition and processing. According to the specific technical scheme, the integrated bio-electricity signal acquisition chip is used for generating an alternating current excitation signal with a specific frequency and a fixed amplitude through an internally integrated excitation source; continuously applying an alternating current excitation signal to one or more target electrodes through an internal analog switch array; the integrated bio-electricity signal acquisition chip is used for acquiring a mixed digital signal from a target electrode, and the mixed digital signal is formed by superposing a bio-electricity signal, a noise signal and an impedance response signal generated by an alternating current excitation signal on target electrode impedance; and the microcontroller unit is used for extracting electrode impedance information from the mixed digital signal and recovering the bio-electricity signal.

A pulsed electric field multi-electrode ablation apparatus, comprising: an ablation catheter (1), which comprises a catheter (1100), and three or more electrodes that are arranged on the catheter (1100); a pulse energy generator, which is electrically connected to the electrodes; and an impedance measurement component, which is electrically connected to the electrodes, wherein the pulse energy generator can generate a pulse wave between any two electrodes; and the impedance measurement component can measure the impedance between any electrodes and / or between any electrode and an external electrode. The pulsed electric field multi-electrode ablation apparatus can provide accurate information of an electrode attachment condition for a user, such that the electrode attachment condition can be adjusted to an ideal state, and after a pulse wave is released between the electrodes by means of the pulse energy generator, a more ideal treatment effect can be obtained.

The invention provides a lower electrode assembly, semiconductor process equipment and a process method, and the lower electrode assembly comprises a bearing part which is used for bearing a wafer; the adjusting electrode is arranged in the bearing part, and the adjusting electrode comprises a plurality of sub-electrodes arranged in the same plane; the impedance adjusting device comprises a plurality of impedance adjusting units, all the impedance adjusting units and all the sub-electrodes are correspondingly arranged and electrically connected, and each sub-electrode and the corresponding impedance adjusting unit are used for being connected between a radio frequency power supply and the ground to form a radio frequency sub-loop; and the impedance adjusting unit is used for changing the impedance of the corresponding radio frequency sub-loop so as to change the current in the corresponding radio frequency sub-loop. According to the lower electrode assembly, the impedance adjusting units and the sub-electrodes are arranged, so that a plurality of radio frequency sub-loops which are connected in parallel can be formed, the process rate of each area is adjusted, the process rate of each area is consistent, and the uniformity of the process rate is improved.

The application provides a kind of early warning system and method of radial artery compression hemostat based on multiple sensors, belongs to complication early warning technical field.The method comprises the following steps: S1, multiple types of physiological signals in the radial artery compression area are synchronously collected and digitized;S2, the temperature at the proximal end and the temperature at the distal end are subjected to discrete wavelet transform;the pulse signal is subjected to time domain analysis, and the pulse amplitude is extracted;S3, a temperature distribution model of the compression area is constructed based on the temperature difference signal;S4, the resistivity distribution of the compression area is reconstructed through the electrode impedance signal, and the bleeding position is located;S5, the pressure change rate is calculated based on the pressure digital signal;the pulse amplitude attenuation rate is calculated based on the pulse amplitude;the pressure change rate, the temperature gradient vector, the pulse amplitude attenuation rate and the bleeding index are fused through a weighted summation formula, and a comprehensive risk value is obtained.The application improves the complication-related parameter coverage rate through multiple sensors, and improves the timeliness and accuracy of complication early warning.

The present invention provides an automatic calibration method and system for neutral electrode impedance detection of a high-frequency electric knife, and relates to the technical field of neutral electrode detection. The method specifically comprises the following steps: S1: obtaining an optimal resonant frequency; S2: when the frequency of an excitation signal source is the optimal resonant frequency, recording a plurality of second voltages by switching a preset impedance connected between two neutral electrodes, and obtaining a voltage-impedance fitting curve by performing interval curve fitting according to a mapping relationship between the preset impedance and the second voltage; S3: when obtaining a measured voltage obtained by performing neutral electrode impedance detection at the optimal resonant frequency, performing impedance calibration on the voltage-impedance fitting curve according to the measured voltage, so as to avoid calibration errors and improve the calibration rate.

The invention discloses a pole piece, a battery and electric equipment, the pole piece comprises a pole piece main body and at least one tab connected with the pole piece main body, the pole piece main body comprises a current collector and an active material coated on the surface of the current collector, the pole piece main body comprises at least two areas in a first direction, and the active materials coated on the at least two areas are different; the at least two regions include a distal region distal from the tab, the active material of the distal region including secondary particles, where the secondary particles are formed from a plurality of primary particles. According to the pole piece, the battery and the electric equipment provided by the invention, the electrode pole piece led out from the same side of the tab is divided into at least two regions, the at least two regions comprise the far-end region far away from the tab, and the active material of the far-end region comprises the secondary particles formed by the primary particles; the problem of uneven distribution of current density and electrode impedance of the side close to the tab and the side far away from the tab in the electrode led out from the same side of the tab can be solved, so that the electrochemical performance of the electrode is improved.