71 results about "Conduction time" patented technology

The invention relates to the technical field of deep learning, in particular to a dialysis hypotension risk prediction system and method based on deep learning, and the system comprises a multi-point signal collection module, a signal processing module, a multi-scale causal expansion convolutional network prediction module, an osmotic pressure correction module and a dialysis plan automatic adjustment module. The method comprises the following steps: synchronously collecting physiological signals of a patient through a finger tip photoelectric volume sensor and a radial artery piezoelectric sensor array, carrying out band-pass filtering and morphological refinement processing on the signals, extracting features, and calculating pulse wave conduction time and a change rate thereof; inputting the characteristic parameters into a multi-scale causal expansion convolutional network to predict the hypotension risk in dialysis; dynamically correcting the prediction result according to electrolyte monitoring data; based on the corrected risk, a hierarchical response strategy is adopted to automatically adjust dialysis parameters, a multi-scale causal expansion convolutional network is adopted to capture physiological parameter changes on different time scales at the same time, and high-precision prediction of hypotension is achieved.

The invention discloses an arteriosclerosis detection method, device and system and an arteriosclerosis detector, and relates to the technical field of medical instruments.The method comprises the steps that after carotid artery pulse waveforms and femoral artery pulse waveforms are subjected to preprocessing and differential processing, division is conducted according to heartbeat cycles; acquiring a carotid artery signal maximum value and a femoral artery signal maximum value in each heartbeat cycle; determining conduction time in each heartbeat cycle according to the carotid artery signal maximum value and the femoral artery signal maximum value in each heartbeat cycle; according to the distance between the carotid artery measuring point and the femoral artery measuring point and the conduction time in each heartbeat cycle, the conduction speed of the pulse wave of the tested person in the arterial system in each heartbeat cycle is determined; determining an average conduction velocity according to the conduction velocity of the pulse wave of the testee in the arterial system in each heartbeat cycle; and determining the arteriosclerosis degree according to the average conduction velocity. The technical problem of low arteriosclerosis measurement precision in the prior art is solved.

A high-safety transistor testing system and method with nanosecond-level delay is disclosed, belonging to the field of transistor testing. It enables transistor characteristic testing under arbitrary drain voltage stress values, drain voltage stress durations, and load currents based on nanosecond-level measurement delays, while ensuring the safety of the testing system and personnel. The circuit includes: a switch. S 1, S 2, S 3. Resistance R A , R C Schottky diode D 1, D 2. Power Inductor L ,power supply V DD Control switch S 1. The conduction time can control the high voltage that the subsequent circuit can withstand. V DD Duration; control switch S 2. On-time can control the power inductor L Current value at the end of charging; test switch S From the voltage and current of 3, we can determine the switch. S 3. Switching transient characteristics, on-resistance characteristics, etc. Simulation and experiments show that the measurement delay of switching to the test state after the drain voltage stress ends is on the order of nanoseconds, and there is no situation of "accidental opening of series switch leading to large current conduction", so the circuit safety is higher.

The application relates to a critical conduction mode control method of a totem-pole PFC converter, which utilizes energy equivalence to determine the resonance process of inductor current at switching commutation, carries out totem-pole Boost inductor current value estimation, and on this basis, utilizes a current zero-crossing point prediction algorithm to calculate the turn-on and turn-off time to generate corresponding active tube-synchronous rectifier tube commutation dead time T d,f , synchronous rectification conduction time T SR , rectifier tube-active tube commutation dead time T d,r ; the PWM drive signals of high-speed switching tubes Q1 and Q2 are generated by T on , T d,f , T SR , T d,r ; the power frequency drive signals of low-speed switching tubes Q3 and Q4 are generated by comparing the input alternating voltage v ac with a hysteresis comparison loop and 0. The method can effectively get rid of the dependence on a current zero-crossing detection circuit and a current sensor, reduces the cost and improves the system stability.

Implantable medical device for stimulating a heart includes a proximal electrode pole, and first and second distal electrode poles. During operation, the device performs: a) detecting an intrinsic atrial contraction of the heart; b) detecting an intrinsic ventricular contraction of the heart; c) determining a first intrinsic atrioventricular conduction time between i) the intrinsic atrial contraction or the stimulation of the atrium and ii) the intrinsic ventricular contraction detected with the first distal electrode pole; and determining a second intrinsic atrioventricular conduction time between i) the intrinsic atrial contraction or the stimulation of the atrium and iii) the intrinsic ventricular contraction detected with the second distal electrode pole; d) setting a stimulated atrioventricular conduction time for stimulating the ventricle of the heart with the first and / or second distal electrode poles, the stimulated atrioventricular conduction time being shorter than the shorter of the first and second intrinsic atrioventricular conduction times.

This invention discloses an intelligent psychological guidance system for harmonizing the Qi of the internal organs based on TCM emotional differentiation, belonging to the field of medical electronic equipment. The system includes a multi-node physiological signal acquisition module, a central control and data processing module, and an acoustic intervention output module. The system synchronously acquires multi-channel bioimpedance, volumetric pulse wave, and electrocardiogram signals, extracts pulse wave conduction time and local blood perfusion index, constructs Qi characteristic parameters, and maps them to generate emotional tags. The central control module locks the target resonance unlocking frequency according to the tags, modulates low-frequency vibrations with reference audio to synthesize a multimodal signal, and further combines physiological pulse transmission delay to perform phase compensation, controlling the precise output of the intervention signal during ventricular diastole. Steady-state determination and closed-loop tracking are performed based on the dynamic gradient of impedance variance. This invention achieves objective quantification of TCM differentiation and ensures high-precision physical alignment between intervention energy and the hemodynamic state of the internal organs.

A method that selects high-quality data within recorded signals from patient monitoring devices, where portions of the signals may be corrupted by noise and should therefore be excluded. Signals are compared to models of expected signal characteristics, and portions of the signals that do not match the models may be excluded. Some models may check for expected relationships between signals from different devices. One such model identifies feature points in two signals from two different devices and calculates the time difference between each feature point in one signal and the earliest subsequent feature point in the other signal; data is excluded if this time difference exceeds an expected range. For example, an expected relationship between electrocardiogram and blood pressure signals is that the R-wave peak should be followed by a blood pressure peak within an expected delay time (the pulse transit time); this check can exclude invalid ECG / BP data.

The invention relates to the technical field of pulse power, in particular to a time sequence synchronous trigger control method for a multi-path pulse switch of an LTD module, which comprises the following steps: S01, measuring the inherent delay time of each discharge branch in the LTD module from trigger signal input to gas switch conduction; and S02, inputting the measured inherent delay time value of each branch into a pulse time sequence controller as a compensation parameter, and setting the delay time of each output channel of the pulse time sequence controller. Through system calibration and programmable delay compensation of the pulse time sequence controller, in combination with high-precision time sequence control of the FPGA, the multi-way switch conduction time deviation can be controlled at the nanosecond level, the energy synthesis efficiency is greatly improved, inductance isolation transmission is achieved through magnetic ring coupling, traditional resistance isolation is replaced, pulse leading edge distortion is avoided, and the energy synthesis efficiency is improved. And meanwhile, high-voltage isolation safety is guaranteed, and trigger signal transmission quality is stable.

The application belongs to the field of heart disease treatment and natural medicine compound, and provides application of bufalin or a pharmaceutically acceptable salt thereof in preparation of a medicine for treating reperfusion arrhythmia. Experiments in vitro and in vivo prove that bufalin inhibits L-type calcium channels in a concentration-dependent manner, reduces extracellular calcium ion inflow, and further reduces the incidence of ventricular arrhythmia, arrhythmia, reduces ventricular conduction time, increases left ventricular conduction velocity, and reduces ventricular conduction dispersion; and provides a new drug selection for the treatment of reperfusion arrhythmia.

The invention discloses a cycle-by-cycle current pre-estimation protection method and a cycle-by-cycle current pre-estimation protection system for a multiphase TLVR circuit, and after pre-storage of current change rates under different working conditions is completed, the cycle-by-cycle current protection system orderly executes the following steps under unified scheduling of a state machine: each phase of inductive current is sampled by an ADC and then sent to an inductive current real-time calculation module; meanwhile, a PWM signal is received; when a certain phase of PWM signal is at a high level, the inductive current real-time calculation module performs cycle-by-cycle current calculation by taking a digital current value obtained by sampling as an initial value, and outputs an estimated current value; the estimated current value is compared with a preset CBC protection threshold value, and then the conduction time of the phase is adjusted; the current increment is calculated in each clock period, the maximum current value which can be reached in the PWM conduction period is predicted, and protection is carried out in time. According to the invention, the problem of local current peak caused by the coupling effect in the TLVR circuit can be effectively solved, and the influence of driving delay is eliminated.

A pulse wave transit time measurement device includes a pulse wave transit time calculator that calculates a pulse wave transit time based on a peak time difference between an electrocardiographic signal and a pulse wave signal, a posture classifier that classifies time serial data of the pulse wave transit time based on a posture detected by an acceleration sensor, and a fluctuation identifier that sets a reference posture from among classified postures, corrects, in conformity with the reference posture, the time serial data of the pulse wave transit time classified into the posture different from the reference posture, and determines fluctuations in the pulse wave transit time based on the time serial data of the pulse wave transit time in the reference posture and the time serial data of the pulse wave transit time having being corrected.

The present application relates to the technical field of medical monitoring, in particular to an intelligent multi-parameter risk early warning system for critical patients. The system transforms ventricular electrical amplitude sequence and pulse pressure difference sequence in a preset sliding data window to determine relative electrical amplitude sequence and relative pulse pressure sequence. The pulse pressure variability is determined based on the pulse pressure difference sequence in the window. The reference conduction time is determined according to the electrical-mechanical delay sequence in the window. The matching cost matrix is constructed according to the reference conduction time, the relative electrical amplitude sequence and the relative pulse pressure sequence, and the optimal matching relationship is solved. The excitation-response data pair set is constructed according to the optimal matching relationship, and the waveform difference index is determined. The response reverse sequence ratio is determined according to the set. The pulse pressure variability, the waveform difference index and the response reverse sequence ratio are used for hierarchical screening to determine the physiological state and output the corresponding risk warning, thereby significantly improving the early cardiovascular abnormality recognition ability.

The utility model relates to the technical field of medical instruments, in particular to an intelligent wireless medical foot switch circuit and device, a control circuit is provided with a timer, and the control circuit identifies the conduction time of the switch circuit through the timer so as to control a first output end or a second output end to output a control signal. According to the utility model, one pedal switch is used for controlling a plurality of medical devices, so that a plurality of pedal switches are omitted, and the risk of mistakenly touching the plurality of pedal switches is avoided. And the first communication module and the second communication module can be wireless communication modules, so that the interference of a line of the wired foot switch on the examination work of a doctor is avoided, and the risk that the line is infected with bacteria is eliminated. And the control safety and the control efficiency of the medical equipment are effectively improved.

To provide a wearable physiological signal detection system applicable to an application scene such as in-home-care, walking support, labor safety and health management, and voluntary health prediction.SOLUTION: A wearable physiological signal sensing system disclosed in the present invention includes: a system circuit board having an upper surface and a lower surface; a stethoscope installed on the lower surface for sensing a cardiac sound signal of a user; a plurality of electrocardiographic electrodes installed on the lower surface, adjacent to the stethoscope for sensing an electrocardiographic signal of the user; and a blood oxygen concentration analyzer installed on the upper surface for sensing a blood oxygen concentration and a pulse wave signal of the user. The system circuit board is electrically connected to the stethoscope, the plurality of electrocardiographic electrodes, and the blood oxygen concentration analyzer. The system circuit board acquires a pulse wave transmission time of the user through comparison between the electrocardiographic signal and the pulse wave signal or comparison between the cardiac sound signal and the pulse wave signal, and estimates a continuous blood pressure of the user on the basis of the pulse wave transmission time.SELECTED DRAWING: Figure 13(a)

The invention discloses an upper limb artery occlusion assessment method and system based on portable multi-camera equipment, terminal equipment and a medium, and relates to the technical field of artery occlusion assessment. The method comprises the following steps: acquiring a reference signal, a left hand pulse wave signal and a right hand pulse wave signal based on the portable multi-camera equipment; the reference signal, the left-hand pulse wave signal and the right-hand pulse wave signal are synchronized by taking the acquisition time as reference time; performing feature extraction on the reference signal, the left-hand pulse wave signal and the right-hand pulse wave signal to obtain a signal transduction time difference feature and a signal waveform similarity feature; and inputting the signal transduction time difference feature and the signal waveform similarity feature into a pre-trained evaluation model to obtain an upper limb artery occlusion evaluation result. According to the method, the portable multi-camera equipment is used for collecting physiological signals of three positions of a human body at the same time, and the obstruction condition of the upper limb artery is simply, conveniently and accurately evaluated by using the signal transduction time difference characteristic and the signal waveform similarity characteristic.

A blood pressure prediction method and apparatus, an electronic device, and a computer-readable storage medium. The method includes: synchronously collecting physiological signals, the physiological signals include electrocardiogram signals, pulse signals and heart sound signal; extracting features from the physiological signals to obtain signal features, the signal features include pre-ejection duration and pulse wave transit time; and inputting the signal features into a pre-trained blood pressure prediction model to cause the blood pressure prediction model to output a blood pressure prediction result.

The invention discloses an overcurrent protection method applied to a TLVR, and belongs to the technical field of switching power supplies. The method comprises the following steps of: modeling and predicting an inductive current rising process in a PWM (Pulse Width Modulation) conduction process by stages, calculating the maximum allowable conduction time when the inductive current in each stage reaches an overcurrent protection threshold value, and outputting a PWM cut-off signal before the threshold value is predicted to be reached, so that an overcurrent protection mechanism is accurately started in advance. According to the invention, the accuracy and response timeliness of overcurrent protection are improved, and current overshoot is effectively suppressed within a safe range; accurate compensation of the TLVR coupling effect is achieved, and the adaptive capacity and robustness of the system under complex working conditions are enhanced.

This invention discloses an intelligent physiotherapy control system and method based on multi-scenario, multi-element collaboration, relating to the field of physiotherapy technology. The method includes the following steps: performing short-time Fourier transforms on the driving waveform of the magnetotherapy module and the excitation waveform of the phototherapy module respectively, extracting the dominant frequency component, harmonic frequency band, and energy density parameters within each working cycle, and constructing a set of magnetic-optical dual-channel spectral feature vectors; based on the spectral feature vector set, calculating the relative frequency ratio and energy superposition ratio between the dominant frequency point of magnetotherapy and the dominant frequency point of phototherapy and their higher harmonics, obtaining a spectral coupling degree index. This invention achieves quantitative assessment of the risk intensity of magnetotherapy and phototherapy by constructing a joint resonance superposition degree, and dynamically adjusts the waveform timing based on this index. By delaying the rising edge and limiting the conduction time, it achieves peak-shifting control of energy output, effectively reducing instantaneous superposition density and improving physiotherapy safety and system adaptability.

A system and method for contactless determination of pulse-transit time from a received image sequence. The method including: determining hemoglobin concentration (HC) signals over time at a first region of interest (ROI) and a second ROI, the first ROI and the second ROI forming a pair of ROIs, the second ROI located downstream from the first ROI along a common pulse wave path; determining a pulse transit time based on a time difference between peaks in the HC signals; and outputting the pulse transit time. The method can further include determining pulse wave velocity (PWV) using the determined PTT and a distance between the pair of ROIs, and outputting the determined PWV. The method can further include determining an estimate of blood pressure using the determined PWV with a trained machine learning model, and outputting the determined estimate of blood pressure.

The application discloses a brain-muscle function change coupling analysis method based on bidirectional delay compensation, which comprises the following steps: designing an experiment paradigm, collecting signals and pre-processing the signals; determining a bidirectional cortical muscle delay estimation algorithm based on a sliding window and transfer entropy TE, and quantifying the conduction time of the EEG->EMG outgoing path and the EMG->EEG incoming path of the cortical muscle of a test person; performing signal time alignment compensation, calculating the transfer entropy with delay compensation and the average delay compensation transfer entropy, and constructing a directional delay compensation directional cortical muscle connection CMC network based on the transfer entropy with delay compensation and the average delay compensation transfer entropy; extracting evaluation features, and performing brain-muscle function change coupling analysis based on the evaluation features; and the evaluation features are extracted based on the dimensions of the CMC coupling strength, the hemispheric lateralization index and the correlation of the delay-motor function behavior index score based on conduction delay, hemispheric division and task stage. The application also discloses a corresponding system, an electronic device and a computer readable storage medium.

An edge-aligned PWM modulation method includes the following steps: Step 1) Determine the sector according to the synthesized voltage vector and determine the conduction sequence of PWM according to different sectors; Step 2) Calculate the action duration of the effective vector according to the synthesized voltage vector; Step 3) Insert the U7 vector based on the known action time of the effective vector; Step 4) Perform phase-shifting operations according to different sectors. The present invention solves the problems existing in the phase current sampling and reconstruction process in the existing single-bus current system, such as inaccurate reconstruction, increased extra conduction times, dependence on motor model parameters, high cost, large volume, etc. Compared with the conventional method, the method provided by the present invention is easy to implement, has a small amount of calculation, does not increase the switching times of power devices, and improves the three-phase current reconstruction accuracy.

The application relates to the technical field of wearable medical devices, in particular to a sleeveless continuous blood pressure monitoring method based on fusion of double-path pulse wave transit time and posture. The sleeveless continuous blood pressure monitoring method based on fusion of double-path pulse wave transit time and posture comprises the following steps: S1, device wearing and system initialization; S2, multi-modal signal synchronous acquisition; S3, signal pretreatment; S4, effective measurement state judgment; S5, wrist and heart height difference calculation; S6, pulse wave feature point recognition and transit time calculation; S7, initial blood pressure value calculation; S8, hydrostatic pressure correction; S9, result output and storage; and S10, returning to step S2 and performing next blood pressure measurement. The technical problems that blood pressure monitoring cannot be continuously measured, is easily disturbed by body position changes, has low measurement precision and lacks individualized calibration in the prior art are solved.

The vital sign detection device of the present invention includes one or more sensors, which can detect a plurality of vital sign signals of a test subject in a non-contact manner, and output corresponding a plurality of vital sign information, thereby achieving fast and accurate vital sign detection. The invention also relates to a combined multi-functional detection device, which includes a camera, a radar sensor, an infrared sensor and a sensor driving unit, used for measuring vital signs. The invention also provides a non-contact blood pressure measurement method and device. The method includes receiving radar echoes and video signal streams at first and second parts, extracting first and second pulse wave signals therefrom, obtaining a measured pulse wave transit time, matching the measured pulse wave transit time with a reference pulse wave transit time, and obtaining a blood pressure value.

This invention relates to the field of medical monitoring technology, specifically to an intelligent multi-parameter risk early warning system for critically ill patients. The system transforms ventricular amplitude and pulse pressure sequences within a preset sliding data window to determine relative amplitude and relative pulse pressure sequences; it then determines pulse pressure variability based on the pulse pressure difference sequence within the window; it determines a reference conduction time based on the electromechanical delay sequence within the window; it constructs a matching cost matrix based on the reference conduction time, relative amplitude, and relative pulse pressure sequences, and solves for the optimal matching relationship; it constructs an excitation-response data pair set based on the optimal matching relationship and determines a waveform difference index; it determines the response inversion ratio based on the set; and it performs graded screening based on pulse pressure variability, waveform difference index, and response inversion ratio to determine physiological status and output corresponding risk warnings, thereby significantly improving the ability to identify early cardiovascular abnormalities.

The invention relates to the technical field of inductance measurement, in particular to an inductance value measurement method based on a PWM signal, which comprises the following steps: setting the complete conduction time of a PMOS transistor; calculating a first loop current of the sampling resistor after the PMOS transistor is completely conducted; applying the PWM signal of the preset amplitude voltage to the grid electrode of the PMOS tube; acquiring a voltage corresponding to a sampling resistor of the to-be-measured inductor in a preset discharge interval time after the rising edge of the PWM signal starts, and obtaining a second loop current value; acquiring the corresponding voltage of the sampling resistor of the to-be-measured inductor in the preset discharge completion time in the PWM signal rise holding stage to obtain a third loop current value; and constructing a to-be-measured inductor prediction model, and predicting the inductance value of the to-be-measured inductor. The method solves the problem that the accuracy is easily influenced by interference factors in inductance measurement in the prior art.

The invention relates to a multi-parameter fusion electrophysiology and hemodynamics real-time monitoring system, through cooperative work of a global synchronous clock generator and a timestamp-based re-alignment mechanism, time-space consistency of a multi-source heterogeneous signal is fundamentally ensured, the synchronous clock generator generates a unified time base signal, and the real-time monitoring of the multi-parameter fusion electrophysiology and hemodynamics is realized. According to the method, sampling actions of all front-end acquisition units are directly driven, an initial phase is locked from a source, a high-speed data preprocessing module prints an accurate timestamp on each data point, and dynamic caching and reordering are carried out through data buffering and alignment queues, so that tiny deviations caused by different transmission paths or processing delay differences of channels are eliminated, and the accuracy of data processing is improved. By means of a double guarantee mechanism of hardware synchronization and software fine calibration, originally dispersed and independent signal streams are integrated into a multi-parameter data stream with completely aligned time axes, accurate and reliable input is obtained, and therefore deep correlation information such as physiological conduction time and coupling strength between a heart beat event and blood vessel response is restored.

The invention discloses an electromagnetic pulse device output characteristic simulation method based on a gas discharge probability model. The method comprises the following steps: establishing an equivalent circuit model and a mechanical structure model of an electromagnetic pulse device; determining an initial electron generation source in the breakdown process of each switch in the electromagnetic pulse device, and calculating an initial electron generation rate and time-space distribution; establishing a breakdown statistical time delay probability distribution model based on a gas discharge probability distribution model; a statistical time delay random sampling link considering a breakdown statistical time delay probability distribution model is added into an equivalent circuit of a strong electromagnetic pulse environment simulation device, switch forming time delay is calculated according to an empirical formula, assignment of switch-on time of each switch is given, equivalent circuit simulation is completed, and voltage waveforms on a load are obtained. Therefore, the problem that simulation of output characteristics of an existing strong electromagnetic pulse environment simulation device is not fine enough is solved, and the randomness of the gas switch discharge process is considered in the method.

According to the ambulatory blood pressure conversion method based on the synchronous cardiac shock signal and the cardiac impact signal, accurate conversion of the ambulatory blood pressure is realized by adopting a non-invasive technical means; according to the method, the aortic valve opening time difference AO-I peak time interval of synchronous cardiac shock signals and cardiac impact signals is adopted to represent the conduction time of the same cardiac cycle vibration signals from the proximal end to the telecentric end, and then the pulse conduction time is accurately represented. The non-linear error between the time difference between the central electric signal R wave and the pulse wave signal and the pulse conduction time in a traditional ambulatory blood pressure conversion method is effectively eliminated, and the prediction result is more accurate. In addition, according to the method, time-frequency characteristics of synchronous cardiac shock signals and cardiac impact signals are extracted, pulse conduction time is assisted for dynamic blood pressure conversion, and the accuracy of the method is further improved.

The invention relates to the technical field of output control, in particular to a constant power control method, device and equipment based on a fixed period and a storage medium, and the method comprises the steps: calculating the current power, dynamically adjusting the conduction time through a PI controller, and carrying out the synergistic effect of synchronous starting and error compensation under the condition that the period is fixed. Adjusting the conduction time of each period in real time according to a PI control result; the output deviation caused by battery voltage fluctuation, control delay and multi-channel asynchronous turn-off is effectively relieved, and the constant power control precision and stability of multi-path output in a fixed period are improved; specifically, the current load resistance is sampled and the average effective voltage is calculated respectively at the turn-on time and the turn-off time of the period k, so that the influence of the voltage fluctuation of the battery on the output can be accurately captured, and a reliable basis is provided for error calculation; the on time of the (k + 1) th period is adjusted through the PI controller, the output power can be balanced in the next period, continuous accumulation of errors is reduced, and the long-term control precision is improved.

The application provides an LLC converter control device and method based on an extended harmonic impedance model. The proposed synchronous rectification method needs to calculate the sampling signals of output direct current voltage and current in a digital signal processor (DSP), and establishes an impedance model in a frequency domain by considering harmonics, so that the synchronous rectification conduction time is accurately calculated. The turn-on time of the synchronous rectification tube is consistent with the primary side switch tube device, and the turn-off time of the synchronous rectification tube is equal to the turn-on time plus the calculated synchronous rectification conduction time. The method not only minimizes the conduction time of the synchronous rectification body diode, has high calculation accuracy, and has high anti-interference on high switching frequency noise, and the proposed method greatly improves the efficiency of the LLC converter.