293 results about "Counting rate" patented technology

The invention discloses a high-speed multi-photon detection system and method. The system comprises a detector and a signal processing circuit, wherein the detector is composed of a window plated with a photoelectric cathode, a micro-channel plate stack and an anode; a plurality of incident photons are converted into a plurality of photoelectrons by the photoelectric cathode, and the photoelectrons are converted into electron cloud by the micro-channel plate stack; the incident electron cloud is divided into multiple paths by three layers of staggered metal strip electrodes of the anode, and charge collection is carried out to obtain charge short pulses of each layer of electrode; the signal processing circuit converts the charge short pulses transmitted by the three layers of electrodes into digital pulse signals, obtains the centroid coordinates of the electron cloud from the digital pulse signals as the abscissa value, the ordinate value and the verification value of the incident photon position, combines the abscissa value, the ordinate value and the verification value based on the screening condition to obtain the target two-dimensional coordinates, and finally obtains the target two-dimensional coordinates. And transmitting to a terminal for imaging display. According to the invention, a plurality of synchronous photons can be detected, the overall counting rate of the detector is greatly improved, and the detection efficiency is improved.

The invention discloses a method and a system for rapidly measuring the concentration of radioactive radon in air in a gas flow mode based on scintillation. According to the method, the net counting rate of alpha particles is measured based on a scintillation method, and the net counting rate of the alpha particles in a corresponding time period needs to be obtained during measurement; in combination with a radon and daughter decay rule and a chamber ventilation condition, establishing a relationship between the net count of alpha particles generated by radon and daughter decay in newly sucked air in a corresponding measurement time period in the measurement chamber and the volume, the pump speed and the original air radioactivity concentration in the chamber; and a corresponding sensitivity coefficient for measuring the radioactive radon concentration of the to-be-measured air is obtained, so that the radioactive radon concentration of the to-be-measured air is obtained in real time. According to the method, the radioactive radon concentration in the air can be rapidly measured in real time under the dynamic gas flow type condition, the measurement time can be greatly saved, the change of the radon concentration in the air can be reflected in time, workers and the public can be protected against the harm of radon radiation, safety production of the nuclear industry can be promoted, and the method has wide application prospects.

The present invention discloses a single-photon detector refrigeration control method and system that is adaptive to temperature and TEC performance changes. The method limits the maximum operating voltage of TEC, monitors the TEC operating voltage and refrigeration temperature in real time, and automatically adjusts the target temperature and APD working bias voltage according to the monitoring results, effectively ensuring that the single-photon detector can still work stably when the working environment temperature is too high or the TEC performance is degraded. At the same time, when the ambient temperature is allowed to return to the normal temperature range, the TEC's refrigeration target temperature can be restored to the initial refrigeration target temperature and the APD's working bias voltage can be adjusted synchronously, so that the performance indicators of the single-photon detector, such as the detection efficiency, dark count rate, and after-pulse probability, will be synchronously restored to normal. In this way, the service life of TEC and single-photon detector equipment can be effectively improved, and the environmental adaptability of the single-photon detector can be improved.

The embodiment of the invention relates to the technical field of nuclear detection and measurement, and discloses a double-label nuclide analysis method and device and a program product, and the method comprises the steps: measuring a standard quenching source, and obtaining an external standard source spectrum index of the standard quenching source; drawing a correction curve by taking the external standard source spectrum index as an independent variable; measuring the double-labeled sample under external gamma source high voltage, and obtaining and calculating an external standard source spectrum index of the double-labeled sample through external gamma source spectrum stripping; determining the counting efficiency of low-energy nuclide, the counting efficiency of high-energy nuclide, the spectrum index of the low-energy nuclide sample and the spectrum index value of the high-energy nuclide sample corresponding to the double-labeled sample under the current quenching level according to the external standard source spectrum index of the double-labeled sample and the correction curve; the method comprises the following steps: measuring a double-labeled sample under double-labeled high pressure to obtain a full-spectrum counting rate and a full-spectrum sample spectrum index of the double-labeled sample; the low-energy nuclide activity and the high-energy nuclide activity of the double-labeled sample are calculated based on the parameters, so that the operability is higher, the accuracy is higher, and the application range is wider.

Disclosed are a neutron dose measurement apparatus and a neutron capturing treatment device. The neutron dose measurement apparatus includes a measurement unit for receiving neutrons and outputting signals, a signal processing unit for processing the signals output from the measurement unit, a counter for counting the signals output from the signal processing unit to obtain a count rate, and a count rate correction unit for correcting the count rate.

The invention relates to the field of crystal detection, and discloses a multifunctional comprehensive scintillation crystal and semiconductor material energy spectrum test system, which comprises a crystal adaptation module for judging the type and size of a placed crystal through an optical identification and parameter matching mechanism, and a signal acquisition module for amplifying, filtering and digitally processing an acquired signal, the signal correction module is used for correcting waveform distortion and baseline drift through a dynamic gain adjustment algorithm of a low-noise pre-amplifier and a multi-channel pulse analyzer; the data analysis module is used for generating an energy spectrum curve according to input signals and calculating energy resolution, counting rate, light attenuation time or carrier mobility, and the environment calibration module is used for dynamically evaluating shading degree, environment light, temperature and electromagnetic interference through an optical sensor and a temperature and humidity detector in the camera obscura and outputting updated calibration parameters. The method has the advantages of improving the detection efficiency, precision and consistency.

The invention relates to the field of LED display screen defect detection, in particular to an LED display screen defect rapid detection method. The method specifically comprises the steps that polarization entangled photon pairs are generated through a first detection assembly, the photon pair coincidence counting rate is measured through an HOM interferometer and a single-photon detector in a second detection assembly, and a photon pair anomaly distribution diagram is generated; establishing a correlation model of the photon pair coincidence counting rate and the electronic state density, and analyzing internal defects of the display screen; an integrated high-speed CMOS camera and a multiband LED annular light source are adopted to collect four-channel image data, and features are extracted to generate an image data abnormal probability graph; and finally, integrating a quantum optical measurement result and an image analysis result through coordinate mapping, judging a final defect area and type based on a decision tree rule, and covering various defect types such as material internal defects, surface reflection abnormity and color unevenness. According to the method, the efficiency and the accuracy of LED display screen defect detection are remarkably improved.

The invention provides an on-site neutron energy spectrum and dose parameterization real-time measurement method. The method comprises the following steps: representing an on-site neutron energy spectrum by using a three-section type function model; constructing simulated field neutron energy spectrums of various moderated levels, measuring by using a detector, and calculating a thermal fast ratio; simulating and calculating a simulated field neutron energy spectrum of the test point through a Monte Carlo model, and obtaining model parameters; establishing a corresponding relation between the model parameters and the thermal fast ratio; a detector is used for measuring the fast neutron pulse counting rate and the thermal neutron pulse counting rate on site, and according to the corresponding relation between the model parameters and the thermal fast ratio, the values of the model parameters are determined in a table look-up or interpolation mode; and calculating a field neutron energy spectrum according to the model parameters, and calculating the field neutron dose by using the field neutron energy spectrum and the neutron fluence-dose conversion coefficient.

The invention relates to a neutron spectrum measurement method and system, and the method comprises the steps: obtaining a neutron signal obtained through the detection of an incident neutron beam through a plurality of detectors; after the neutron signal is processed, a processed signal is obtained; obtaining the neutron counting rate of each detector based on the processing signal; the initial neutron counting rate of the jth energy interval in the incident neutron beam is set as # imgabs0 #, the initial neutron counting rate is substituted into a formula for iterative calculation, and when the absolute value of the difference value of # imgabs1 # and # imgabs2 # is smaller than a preset first threshold value, # imgabs3 # is the neutron counting rate of the jth energy interval in the incident neutron beam; and calculating the neutron counting rates corresponding to the n energy intervals in the incident neutron beam corresponding to each detector in sequence to obtain the neutron energy spectrum of the incident neutron beam. The measuring method is simple in measuring process and high in accuracy.

The invention relates to the technical field of single-photon detection, in particular to a single-photon detector performance parameter measurement method, device and equipment and a storage medium, and the method comprises the steps: building a statistical histogram of time domain interval data, and building the statistical distribution characteristics of the photon counting rate and dark counting of a single-photon detector; the probability of no photon detection event in the duration of the optical pulse and the ideal probability of no dark pulse in a preset time window are defined based on the statistical distribution characteristics, and then the probability of generating a single photon signal by the periodic optical pulse is calculated based on the obtained parameters; and finally, determining a periodic statistical peak count value based on the statistical histogram and the probability of generating the single photon signal by the periodic light pulse, and calculating an average detection photon number and a dark count rate so as to obtain the dead zone time, so that information such as the average detection photon number, the dark count rate and the dead zone time of the single photon detector is simultaneously represented through one-time data acquisition, and the detection accuracy of the single photon detector is improved. The problems that in a traditional method, the data storage amount is large, and cost is high are solved.

The invention provides a dynamic PSD threshold value correction method, device and equipment suitable for digital pulse waveform discrimination, and relates to the technical field of nuclear radiation detection.The method comprises the steps that a current PSD-energy two-dimensional spectrum is obtained through a nuclear radiation detecting instrument, counts in a target energy range in the current PSD-energy two-dimensional spectrum are removed, and the current PSD-energy two-dimensional spectrum is obtained; converting into a one-dimensional PSD spectrum by using a preset formula; determining the position of the maximum peak and the full width at half maximum in the one-dimensional PSD spectrum, determining a PSD threshold value, and resetting the target PSD value range according to the PSD threshold value; and obtaining the target PSD-energy two-dimensional spectrum again, carrying out statistics on the discrimination target ray counting value and the total counting value, and determining a main target ray counting value according to a difference value between the total counting value and the discrimination target ray counting value so as to determine a main target ray counting rate and a discrimination target ray counting rate. By regularly and automatically analyzing the PSD-energy two-dimensional spectrum and dynamically adjusting the PSD threshold value, different particles can be more accurately discriminated, and the particle detection accuracy and efficiency are improved.

A method of determining downhole formation oil saturation and three-phase holdup is described. The method includes lowering a pulsed-neutron logging tool downhole with a near detector and a far detector. The method further includes measuring a carbon to oxygen ratio from the near detector, measuring a carbon to oxygen ratio from the far detector, measuring a ratio of inelastic count rates, and plotting the measured ratios in a prismatic grid. The method further includes visualizing the fluid volumetrics around the pulsed-neutron logging tool.

The invention belongs to the technical field of digital signal processing, and particularly provides a nuclear pulse amplitude extraction method based on parameter identification and a nuclear pulse analysis system, which are used for solving the problem that the precision of an energy spectrum diagram is reduced due to baseline drift of a nuclear pulse signal and pulse accumulation and discarding, so that the energy resolution and the counting rate of the nuclear pulse energy spectrum diagram are improved. According to the method, accurate capture and processing of nuclear pulse signals can be realized, an original sampling sequence signal is processed by using a filtering method, the influence of baseline drift is reduced, parameter identification and amplitude extraction are carried out on stacked pulses processed by a combined filtering method by using a parameter identification model, and a high-precision spectrogram is generated; therefore, the energy resolution and the counting rate of the system are improved, and powerful technical support is provided for the fields of nuclear physics research, nuclear energy application, nuclear radiation detection and the like.

The invention discloses a two-photon N00N quantum state intelligent regulation and control device and method, and the device comprises an intelligent regulation and control module, and an entangled photon pair generation module, an HOM interferometer and a data collection module which are connected in sequence, and the entangled photon pair generation module transmits polarized orthogonal entangled photon pairs to two light paths in the HOM interferometer respectively; the data acquisition module is used for detecting and counting photons output by the two light paths respectively; the intelligent regulation and control module controls the first electric control time delay line on one light path and the electric control polarization controller on the corresponding light path so as to regulate the light path difference of the two light paths and the polarization state of photons output by the corresponding light path; every time control is completed, a second electric control time delay line on the other light path is controlled to carry out time delay scanning according to a set rule, and a coincidence counting rate and HOM visibility are obtained; and according to the coincidence counting rate and the HOM visibility, determining whether the two-photon N00N quantum state generated under the control is good or bad. According to the invention, intelligent regulation and control of the two-photon N00N quantum state quality can be realized.

The invention relates to the technical field of data calibration, in particular to a neutron fluence response calibration method based on a neutron generator reference radiation field, and the method comprises the steps: collecting a counting rate and a neutron fluence rate at each moment in each monitoring period through a neutron detector and a neutron generator; data of each environmental parameter around the reference radiation field at each moment in each monitoring period are obtained; recording each monitoring period and a plurality of monitoring periods before the monitoring period as historical periods; determining the measurement error of each historical period; obtaining the measurement interference degree of each environmental parameter in each monitoring period; and calculating the scattering interference degree of each environmental parameter in each monitoring period to obtain a calibration counting rate, and carrying out real-time calibration on the neutron fluence response. According to the invention, the interference influence of different environmental factors on the measurement result of the neutron detector can be quantified through dynamic environmental changes, the measurement result of the neutron detector is calibrated in real time, and the measurement accuracy of neutron fluence response is improved.

The invention relates to a Lu-177 activity direct measurement method, a Lu-177 activity direct measurement device and a processor. The method comprises the following steps: constructing a first calculation model for calculating the detection efficiency of a Lu-177 sample; the Lu-177 sample and the blank sample corresponding to the Lu-177 sample are measured, and the counting rate of the Lu-177 sample under different coincidence conditions is obtained; calculating detection efficiency based on the counting rate and a first calculation model; and calculating the activity of the Lu-177 sample based on the detection efficiency, the counting rate and an activity calculation model. Compared with the prior art that the low uncertainty level can be achieved only by carrying out dilution measurement in a laboratory or the high uncertainty level of field direct measurement is achieved, the method has the advantage that the accurate activity of the Lu-177 sample can be obtained by carrying out direct measurement and calculation in the laboratory or the field on the premise that dilution is not carried out. The method meets the requirements of simple and convenient sample preparation, recoverable nuclide and low uncertainty.

The invention relates to a signal acquisition device of a cadmium zinc telluride detector based on multiple channels, which is characterized in that a multi-channel parallel processing unit, a dynamic baseline drift correction unit, a self-adaptive dead time control unit and an energy spectrum reconstruction and trailing suppression unit are mutually matched; reverse compensation current can be injected into each channel through the dynamic baseline drift correction unit so as to adjust the output of each channel, and low-frequency noise interference is eliminated in combination with a digital filtering algorithm. The dead time can be dynamically adjusted according to the current channel counting rate through the self-adaptive dead time control unit, multiple counters are started to work alternately in a first counting rate mode, and counter resources are combined in a second counting rate mode to improve the resolution; through the energy spectrum reconstruction and trailing suppression unit, a charge collection curve can be fitted through correlation analysis of timestamps and amplitude data, hole trailing signals are recognized, counter shielding logic is triggered, related noise interference is reduced on the whole, and signal collection accuracy is improved.

A method of determining downhole formation oil saturation and three-phase holdup is described. The method includes lowering a pulsed-neutron logging tool downhole with a near detector and a far detector. The method further includes measuring a carbon to oxygen ratio from the near detector, measuring a carbon to oxygen ratio from the far detector, measuring a ratio of inelastic count rates, and plotting the measured ratios in a prismatic grid. The method further includes visualizing the fluid volumetrics around the pulsed-neutron logging tool.

The invention discloses a single-photon detector post-pulse probability suppression method and system, and the method achieves the measurement of the arrival time of a detection pulse after a previous detection pulse, abandons the detection pulses in a certain time range, reduces the post-pulse probability, does not need to close a gate signal and hardware processing, and does not affect the performance of a detector. The post-pulse probability time distribution characteristics of the single-photon detector can be identified by means of a time periodic folding measurement scheme, so that the optimal suppression time window of the post-pulse probability of the single-photon detector can be reasonably adjusted according to the relationship between post-pulse probability distribution and the saturation counting rate, and the optimal detector performance is realized. The method has the characteristic of universality, is not only applied to a sine gating detector, but also can be applied to scenes such as a rectangular gating detector and a free operation detector which need to further suppress the post-pulse, and does not affect the original detection process.

The invention discloses a muon detector with variable scintillator spacing, which comprises a supporting base, and a bottom plate is arranged at the upper end part of the supporting base; the lower-layer detection part is fixedly arranged at the end part of the bottom plate, a multi-stage mechanical telescopic mechanism is arranged on the bottom plate, and an upper-layer detection part is arranged at the end part of the multi-stage mechanical telescopic mechanism; the main control data acquisition system is electrically connected with the multi-stage mechanical telescopic mechanism, the upper-layer detection part and the lower-layer detection part, and is used for setting and acquiring a distance value between the upper-layer detection part and the lower-layer detection part; and calculating according to the collected real-time spacing value, and performing corresponding data correction and image reconstruction according to the effective detection range and the optimal detection area under the current configuration. According to the method, the spatial resolution and the counting rate can be dynamically adjusted, so that the performance limitation caused by a fixed spacing design is broken through, and the comprehensive efficiency in a complex detection task is remarkably improved.

A nuclear instrumentation device (100) comprises: a waveform discrimination circuit (41) that extracts a neutron-derived pulse signal from a pulse signal detected by a detector (1); a pulse count circuit (42) that periodically counts the neutron-derived pulse signal; a count rate conversion circuit (43) that converts the pulse count value into a count rate; a zero count circuit (45) that calculates a continuation period in which the pulse count value of the pulse count circuit (42) becomes zero; a time constant selection circuit (46) that selects a time constant according to the period calculated by the zero count circuit (45) when the pulse count value in the pulse count circuit (42) is zero, and that selects a larger time constant as the count rate decreases and a smaller time constant as the count rate increases when the pulse count value is not zero; and an integration circuit (47) that calculates the count rate of neutrons in each period by using the selected time constant, the abovementioned circuits being composed of digital circuits.

The invention provides a flow cytometer light path calibration method, which belongs to the technical field of flow cytometers, and comprises the following steps: firstly, collecting light path detection original data of standard fluorescent microspheres, including laser spot position coordinates, detector output voltage value, dark counting rate and signal counting rate; then establishing a detection channel conversion cost matrix, and calculating an optimal light path detection sequence by using a traveling salesman problem optimization algorithm; adjusting the positions of a laser, an optical filter and a detector according to the optimal sequence, and obtaining optical path calibration data; the collected parameters are substituted into an optical path parameter optimization equation set to be solved, and an optical path collimation coefficient, a detector response coefficient, a signal crosstalk coefficient and an optimal gain value are obtained; and finally, respectively adjusting the position of the laser, the working voltage of the detector, the position of the optical filter and the voltage of the photomultiplier according to the coefficients to finish the accurate calibration of the optical path. The problems that an existing method depending on artificial experience is low in efficiency and overall optimization of a system level is difficult to achieve are solved.

The invention relates to the technical field of neutron imaging and detection, in particular to a data processing method for a neutron imaging detector based on a micro channel plate (MCP), and more particularly relates to a waveform analysis and example reconstruction algorithm for white light neutron resonance imaging. Comprising a waveform analysis step and a case reconstruction step, in the waveform analysis step, an advanced waveform recognition technology is adopted, off-line analysis is carried out on signal waveforms on an anode plate of the neutron imaging detector, and the signal waveform of each electron group is accurately recognized; in the case reconstruction step, the signals are grouped and paired based on a waveform analysis result, and an accurate position reconstruction model is constructed to obtain an accurate coordinate of an electron group hit position; the method not only improves the imaging precision and the counting rate, but also optimizes the data processing flow, adapts to the condition of high counting rate, improves the overall performance of the system, expands the application field, and provides powerful support for the development and application of the neutron imaging technology.

The invention discloses a dynamic threshold adjusting system based on a silicon photomultiplier receiver and a laser radar, and belongs to the technical field of photoelectric detection. According to the system, an incident light signal is captured in real time through a silicon photomultiplier receiver, a pulse counting rate is extracted by a signal processing module to represent ambient light intensity, and an SiPM detection threshold value is adjusted based on a dynamic feedback mechanism: when background light is enhanced, the threshold value is increased to suppress noise pulses; when the background light is weakened, the threshold is reduced to preserve the weak signal. A grey-scale map generation module is introduced, noise distribution of multi-channel SiPM is converted into a two-dimensional grey-scale map through a space mapping algorithm, and accurate positioning of a noise source and collaborative optimization of a regional threshold are achieved.

The invention discloses a digital silicon photomultiplier tube, comprising: a pixel array module, a logic circuit module, a counter / time digital converter, a counting rate comparison and judgment module and an enable control module; the digital SiPM sensor of the invention can compare and judge the current counting rate with the rated threshold counting rate, and feed back the comparison result to the enable control module, and the enable control module outputs an enable for adjusting the number n of effective pixels receiving photons to the pixel array module, thereby changing the probability of the effective pixel array in the pixel array module receiving photons to adjust the current counting rate of the counter / time digital converter, so that the current counting rate is within a suitable range, avoiding the occurrence of pile-up distortion, improving the accuracy of distance measurement, and reducing the power consumption required under the same detection effect.

A nanoscale temperature detector comprising a diamond sensing probe (1) having a lateral dimension of at least 200 nanometers and having a sensing tip (2) with a radius of curvature (R) of less than 100 nanometers, less than 10 nanometers or less than 1 nanometer and a plurality of color centers (5) showing temperature sensitive features in the emission count rate. The diamond sensing probe (1) has a lateral dimension of at least 200 nanometers and is connected to a detector system (13) by a mounting structure (6). A thermal isolation barrier (3) thermally separates the sensing probe (1) from the detector system (13).

The invention discloses a medical image coincidence event processing method, system and device, equipment and a medium. The coincidence event processing method for the medical image comprises the steps that an original event is obtained, and the original event is an event composed of single photons and obtained by collecting photons generated by decay of a radioactive tracer through a detector; based on the energy information and the time information of the original events, the original events are discriminated, effective events are obtained, the effective events comprise true coincidence events and random coincidence events, and the true coincidence events are used for medical image reconstruction; determining a time window for the detector to collect photons, and dynamically adjusting the window width of the time window based on the change trend of the event counting rate; the valid events are processed based on the time window to reduce random coincidence events in the valid events.

The application discloses a kind of arbitrary waveform nuclear pulse conversion methods, for the trapezoidal shaping of arbitrary waveform nuclear pulse signal.First, the arbitrary waveform nuclear pulse signal is regarded as the impulse response of rational fraction transfer function system.Second, rational fraction transfer function is decomposed into multiple first-order inertia link and the form of sum, then, multiple first-order inertia link and the form of sum is carried out Laplace inverse transformation into time domain expression, and then its time domain expression is discretized and transformed, then the parameter of discretized expression is obtained using particle swarm algorithm, finally, the transfer function of trapezoidal shaping and shaping recurrence formula are obtained, the trapezoidal shaping of arbitrary waveform nuclear pulse signal is realized to a certain extent, the symmetry of trapezoidal pulse is improved, the accurate acquisition of pulse amplitude is facilitated, the energy resolution of system is improved and the counting rate is improved, which has great significance for improving the precision of radioactivity measurement.

The invention belongs to the technical field of uranium concentration, and particularly relates to a uranium concentration factory product abundance real-time monitoring method, device and system. The method comprises the following steps: introducing UF6 gas to be measured into a measuring container, and obtaining the total count rate of gamma rays in the measuring container by using a NaI detector; acquiring abundance of the UF6 gas according to a background obtained in advance, the total count rate, a scale coefficient and the pressure and temperature in the measuring container; wherein the background is determined by the following steps of: measuring counting rates of characteristic gamma rays in the measuring container under different pressures by using a NaI detector to obtain a plurality of counting rates; the lower the pressure is, the longer the measurement time of the NaI detector is; and fitting the counting rate of the corresponding gamma ray when the pressure is zero according to the plurality of obtained counting rates and the corresponding pressure to obtain the background. According to the invention, the dependence of product abundance monitoring on operators is eliminated, the abundance measurement precision is ensured, and the operation and maintenance cost is reduced.

The invention provides an online diagnosis and repair method for a uranium mine gamma ray monitoring device, and the method comprises the steps: determining the respective counting rate correction values of a plurality of detectors based on the current working temperature of the uranium mine gamma ray monitoring device, a preset temperature compensation model, and the counting rate detection values of the plurality of detectors; based on the respective counting rate correction values of the plurality of detectors, the detection efficiency of each detector is determined, and the detection efficiency comprises static detection efficiency and dynamic detection efficiency; and if the detection efficiency of any first detector in the plurality of detectors is deviated from the detection efficiency of a specified second detector in the plurality of detectors, circuit parameters of the first detector are adjusted based on the deviation, so that the detection efficiency of the first detector after the circuit parameters are adjusted is consistent with the detection efficiency of the second detector. According to the technical scheme, the measurement precision and the detection efficiency of the uranium ore gamma ray monitoring device in continuous operation are improved, and the uranium ore sorting energy efficiency is improved.