17 results about "Pulse rise time" patented technology

The invention discloses a ballistocardiogram signal feature engineering method for blood pressure prediction, and the method comprises the steps: extracting multi-dimensional BCG signal features from the four aspects of time domain, frequency domain, fluctuation characteristics and waveform characteristics, including heart rate variability time domain and frequency domain related features; fluctuation mode characteristics, such as zero-crossing rate, absolute instantaneous slope, average extreme point number, average accumulated amplitude change and the like; and waveform characteristics of J peak, I valley, K valley and the like, such as pulse rise time, pulse fall time, ballistocardiogram pulse deviation, J peak-K valley amplitude deviation and the like. According to the method, a composite feature set of the BCG signals can be obtained, the accuracy of blood pressure prediction based on the BCG signals can be remarkably improved on the premise of being visual, clear and high in interpretability, and reliable support is provided for early recognition and real-time monitoring of hypertension.

A method to enhance the functionality of a battery through the use of a pulsing apparatus. The pulsing apparatus configured to improve cell conditioning, maintain battery cells, and overall cell function through pulsing a selected current into and out of a battery. The pulsing selected to deliver a predetermined number of pulses to the battery. The pulses having a slew rate of at least 0.1 A / μs, a pulse width between 1 μs and 10 ms with a pulse rise time of at least 1 μs to alter a current of the battery. Preferably the predetermined number of pulses is between 100 pulses per second and 1 pulse per minute.

The invention discloses a multi-objective optimization design method for a high-voltage nanosecond pulse adder, and aims to solve the problem that the prior art depends on experience trial and error and is difficult to consider multiple objectives such as fast leading edge, high efficiency, portability and reliability. The method comprises the following steps: firstly, building a simulation and experiment platform, and acquiring output waveform data for changing topological parameters; constructing a physical model of the influence rule of the parasitic parameters on the pulse rising edge time and the voltage gain, and establishing a power supply efficiency prediction model based on a deep neural network; taking the minimization of the pulse rising edge time and the maximization of the voltage gain and the energy efficiency as targets, constructing a particle swarm optimization multi-target optimization model in combination with the model, and obtaining a Pareto optimal solution set under the constraints of portability and parasitic parameters; and finally, carrying out experimental verification iteration to obtain an optimal scheme. According to the invention, the design period is obviously shortened, the multi-target conflict is effectively balanced, the rising edge time is shortened, the energy efficiency is improved, the voltage gain is improved, the portability is enhanced through the modular design, and the wearable application is compatible.

The invention relates to the technical field of electric power, and provides a fault position determination method and device and a computer readable storage medium. The pulse frequency, the pulse rising edge duration and the polarity of each traveling wave pulse in the multiple traveling wave pulses in the target time period are obtained; determining at least one reflection traveling wave pulse of a target traveling wave pulse in the plurality of traveling wave pulses according to the pulse frequency, the pulse rising edge duration and the polarity of each traveling wave pulse in the plurality of traveling wave pulses; determining a target distance according to the first moment and the second moment; the target distance is the distance between the fault position on the power transmission line and the fault position determining device. The accuracy of determining the fault position can be improved.

The invention relates to a modeling and application method of a nonlinear capacitance model of a DSRD device, and the modeling method comprises the following steps: splitting a nonlinear capacitor, and building a current expression of the nonlinear capacitor of the DSRD device; according to the current expression of the nonlinear capacitor of the DSRD device and the working principle of the DSRD device, constructing a nonlinear capacitor to-be-fitted model of the DSRD device; and according to the optimal model CV curve, updating to-be-fitted parameters in the nonlinear capacitance to-be-fitted model of the DSRD device to obtain the nonlinear capacitance model of the DSRD device. According to the nonlinear capacitance model of the DSRD device established by the modeling method of the nonlinear capacitance model of the DSRD device provided by the invention, accurate fitting of the nonlinear capacitance of the DSRD device in a full voltage range can be realized, and accurate simulation of pulse rise time can be realized.

This invention discloses a high-voltage nanosecond pulse shaping device and method based on magnetic devices. The device includes: a first magnetic transmission line and a second magnetic transmission line, with their input ends connected in parallel and connected to an initial pulse source; the output end of the first magnetic transmission line is connected to a load terminal; the output end of the second magnetic transmission line is short-circuited to ground; the first magnetic transmission line includes a first magnetic ring arranged along the axial direction and an outer magnetic field coil; the second magnetic transmission line includes a second magnetic ring arranged along the axial direction. Based on the current-dependent nonlinear permeability effect of the magnetic ring, this device simultaneously achieves pulse rise time compression, fall time truncation, pulse width shortening, and suppression of pre-pulse and tail oscillations through the rising sharpening effect of the first magnetic transmission line and the falling truncation effect of the second magnetic transmission line. This overcomes the limitation of single nonlinear transmission line or magnetic switching technology, which can only optimize single pulse parameters, and can obtain high-quality pulse waveforms at the load terminal.

A pulsed laser system includes a laser that delivers a light pulse to an optical shutter configured to transmit, of the pulse: (a) a first transmitted portion having a rise time of less than 20 ns and a first portion peak power, then (b) a second transmitted portion having an initial power less than the first portion peak power, and then (c) a third transmitted portion having an energy of at least 100 nJ and a duration of less than or equal to 200 ns. A low voltage driver (to control transmission of the first transmitted portion) can be connected to an EOM in the optical shutter in parallel with a high voltage driver (to control transmission of the third transmitted portion), with electrical isolators positioned the outputs of the respective voltage drivers to protect the low voltage driver.

A method to enhance the functionality of a battery through the use of a pulsing apparatus. The pulsing apparatus configured to improve cell conditioning, maintain battery cells, and overall cell function through pulsing a selected current into and out of a battery. The pulsing selected to deliver a predetermined number of pulses to the battery. The pulses having a slew rate of at least 0.1 A / μs, a pulse width between 1 μs and 10 ms with a pulse rise time of at least 1 μs to alter a current of the battery. Preferably the predetermined number of pulses is between 100 pulses per second and 1 pulse per minute.

The invention belongs to the technical field of power electronic devices, and particularly discloses a cascade high-voltage pulse trigger circuit based on SiC DSRD. The cascaded high-voltage pulse trigger circuit is formed by connecting a first-stage structure and a second-stage structure in series; the first-stage structure comprises a plurality of branch structures which are connected in parallel, the branch structures are completely the same, and each branch structure comprises a single SiC DSRD and is used for providing a reverse current; the second-stage structure comprises a single SiC DSRD and is used for reversely extracting a plurality of reverse currents gathered by the first-stage structure and generating high-voltage pulses on a load resistor. According to the invention, a plurality of branches are connected in parallel to provide a larger reverse extraction current for a rear-stage (output-stage) SiC DSRD, so that the rise time of an output pulse is reduced; meanwhile, forward pumping is carried out on the rear-stage (output-stage) SiC DSRD through an independent capacitor, larger forward pumping charges are guaranteed, and therefore the output pulse voltage of the single SiC DSRD is increased.

The application discloses a method and system for measuring charge quantity integration by a loop noise elimination method. The method comprises the following steps: judging whether the time constant RCO of a circuit is less than the pulse rising time t r ; if the time constant RCO is less than the pulse rising time t r , measuring the charge quantity integration by the loop noise elimination method, and eliminating the random influence of the non-smoothness of the pulse voltage waveform by using a moving average; and if the time constant RCO is not less than the pulse rising time t r , exiting the measurement of the charge quantity integration.

The invention discloses a method for measuring a (n, alpha) reaction angle differential cross section, and belongs to the technical field of nuclear data measurement. Anode pulse rising time and anode amplitude are obtained through measurement of a screen grid ionization chamber and a gas sample, the projection length, parallel to the neutron incidence direction, of a nuclear reaction event track is obtained through the anode pulse rising time, and one projection length corresponds to two alpha particle emergence angles; the events with the same projection length and different alpha particle emergent angles can be distinguished according to different anode amplitudes, so that according to the anode amplitude-anode pulse rise time two-dimensional spectrum, the events with different alpha particle emergent angles are divided through the V-shaped event area on the two-dimensional spectrum to obtain the number of events; and the to-be-measured reaction angle differential cross section can be obtained by combining the to-be-measured reaction nuclear number and the corresponding neutron flux. The device can be used for measuring the angle differential cross section of (n, alpha) reaction, and has the characteristics that the number of nucleuses of a sample to be measured is large, the detection efficiency is high, and the device is not limited by the placement angle of a detector.

The application provides a magnetic blow-by treatment method, device and welding system. The method comprises: after the start of a first pulse period, performing pulse welding with first welding parameters; obtaining an actual pulse base value voltage; determining whether magnetic blow-by occurs based on the actual pulse base value voltage and a first preset pulse base value reference voltage; if magnetic blow-by occurs, increasing the pulse rise time and the pulse fall time in the next pulse period of the first pulse period, and reducing the pulse peak current, so as to perform pulse welding based on the adjusted pulse rise time, pulse fall time and pulse peak current in the next pulse period, thereby improving the anti-interference ability of the pulse arc to magnetic blow-by, ensuring the one-pulse-one-drop droplet transfer state, enabling the arc to maintain good stability during welding, and thereby reducing or eliminating the influence of magnetic blow-by on the pulse welding efficiency and the pulse welding effect, so that the pulse welding efficiency is higher and the pulse welding effect is better.

This invention relates to a modeling and application method for a nonlinear capacitance model of a DSRD device. The modeling method includes the following steps: decomposing the nonlinear capacitance to establish a current expression for the nonlinear capacitance of the DSRD device; constructing a fitting model for the nonlinear capacitance of the DSRD device based on the current expression and the working principle of the DSRD device; updating the fitting parameters in the fitting model of the nonlinear capacitance of the DSRD device based on the CV curve of the optimal model, thereby obtaining the nonlinear capacitance model of the DSRD device. The nonlinear capacitance model of the DSRD device established by the modeling method provided by this invention can accurately fit the nonlinear capacitance of the DSRD device across the entire voltage range and can achieve accurate simulation of pulse rise time.

The present invention discloses a feature engineering method for ballistocardiogram signal for blood pressure prediction, which extracts multidimensional BCG signal features from four aspects: time domain, frequency domain, fluctuation characteristics and waveform characteristics, including: time domain and frequency domain related features of heart rate variability; fluctuation pattern features, such as zero crossing rate, absolute instantaneous slope, average number of extreme points and average cumulative amplitude change, etc.; and J peak, I valley, K valley and other waveform features, such as pulse rise time, pulse fall time, ballistocardiogram pulse deviation and J peak-K valley amplitude deviation, etc. The present invention can obtain a composite feature set of BCG signals, which can significantly improve the accuracy of blood pressure prediction based on BCG signals under the premise of being intuitive, clear and highly interpretable, and provide reliable support for early identification and real-time monitoring of hypertension.

This invention discloses an online dose monitoring and alarm system and method for boron neutron capture therapy, belonging to the field of radiation dose monitoring technology. It includes at least one set of integrated wireless monitoring probes and a central monitoring platform. The system highly integrates a radiation detection module, a photoelectric conversion module, a high-speed analog-to-digital / digital-to-analog conversion module, an FPGA module, a wireless communication module, and a built-in lithium battery. The FPGA executes a shape discrimination algorithm based on the difference between pulse rise time and / or decay time at the probe end using hardware logic to distinguish neutron / gamma events and calculate the count rate and dose rate in real time. When the monitored value exceeds a preset safety threshold, the high-speed digital-to-analog conversion module drives an LED indicator and / or a buzzer to issue a local audible and visual alarm. Compared with existing technologies, this invention achieves synchronous real-time monitoring of neutron flux and gamma dose, improves alarm response speed, facilitates flexible deployment near the treatment head or patient irradiation field in space-constrained locations, and enhances the safety and accuracy of treatment.

The invention provides a complex pulse signal pulse parameter metering calibration device, which comprises an AD sampling device for acquiring a measured signal and performing AD sampling on the measured signal to generate a sampling signal; the calibration module is used for carrying out metering calibration on the sampling signals at a digital end so as to measure pulse parameters, and the items of metering calibration comprise filtering, feature recognition, pulse envelope monitoring, automatic time window taking and pulse parameter measurement; the traceability module is used for tracing the metrological characteristics of the calibration module at the digital end according to the measurement information of the calibration module; wherein the source is traced to a time frequency parameter based on frequency measurement information, the source is traced to a time interval based on pulse width and pulse delay measurement information, the source is traced to a standard pulse rise time based on pulse rise / fall time measurement information, and the source is traced to a standard square wave amplitude based on pulse top fluctuation measurement information. According to the invention, the pulse parameter metering of the complex coded modulation pulse is completed through a digital means, and the metering efficiency and accuracy are improved.

This invention discloses a continuous repetition frequency (CRLF) ultra-high voltage pulse transformer, comprising an outer cylinder, an oil tank, an input terminal assembly, an output terminal assembly, and a transformer assembly. By rounding the corners of the transformer core, using circular winding of the windings, and incorporating an equalizing ring at the high-voltage end, the problems of tip arcing and corona discharge in ultra-high voltage environments are solved, improving the electric field distribution. The use of a closed-core cage structure for the magnetic core and a tapered winding structure for the secondary windings solves the problem of slow output pulse rise time. The transformer of this invention, with its tubular outer cylinder, can serve as both an oil tank and a transformer assembly mounting point, reducing product size, floor space, and manufacturing complexity. This solves the problems of traditional ultra-high voltage pulse transformers being bulky, heavy, aesthetically unappealing, and structurally complex. Simultaneously, it also functions as a radiation shielding layer, resolving the problem of electromagnetic interference causing damage to the surrounding environment and equipment during online operation.