38 results about "Coincidence circuit" patented technology

The invention belongs to the field of power engineering and provides a symmetrical obtaining method for nodal voltage sensitivity in an alternating-direct current parallel-serial power grid. In the symmetrical obtaining method, on the premise of obtaining an independent vector, a nodal voltage vector and a nodal charging power vector of the alternating-direct current parallel-serial power grid, aunified partial derivative formula is built for obtaining the voltage sensitivity of each node according to a relationship equation of the independent vector and the nodal voltage vector, and a function relationship expression of the nodal charging power vector with respect to the independent vector and the nodal voltage vector, so that the symmetrical obtaining for the voltage sensitivity of allnodes in the alternating-direct current parallel-serial power grid is achieved, thus the symmetrical obtaining method reflects an instigating action of a direct-current feed-in system to active powerand instigated performance to inactive power, and also reflects a purpose that the work of a balancing generator in the alternating-direct current parallel-serial power grid satisfies an objective law of a circuital law.

The invention discloses a channel type radioactive detector with a low detection limit, which is used for a channel type radioactive monitoring system. The channel type radioactive detector comprises a shell, a shielding body arranged in the shell, a plastic scintillator, a first photomultiplier, a first preamplifier, a second photomultiplier, a second preamplifier, a signal processing and controlling unit. Two ends of the plastic scintillator are coupled with two photomultipliers through light guides to output two paths of pulse signals. The signal processing and controlling unit is internally provided with an adder circuit and an accordance circuit, which are used for adding two paths of the pulse signals to detect whether the pulse signals accord with requirements. In the invention, through a signal adding and accordance method and the shielding by using a lead shielding body, the cost can be effectively reduced, the noise is reduced, the signal to noise ratio is improved, the detection efficiency and the sensitivity are improved, and the energy detection lower limit is reduced, so that low-energy nuclides can be more effectively detected and measurement requirements are better met.

The invention discloses a novel system and method of measuring concentration of radon in water. The novel system of measuring concentration of radon in water includes successively connected first Gamma detector, first linear amplifier, first single-channel pulse-height analyzer, first delay shaping circuit and first scaler, and successively connected second Gamma detector, second linear amplifier,second single-channel pulse-height analyzer, second delay shaping circuit and second scaler, wherein the output terminal of the first delay shaping circuit and the output terminal of the second delayshaping circuit are connected to the input terminal of a coincidence circuit; the coincidence output terminal of the coincidence circuit is connected with a third scaler; the novel system of measuring concentration of radon in water also includes a calculation module which is used for calculating the activity concentration C<222><Rn>: C<222><Rn>=n<Gamma Gamma 1> - n) / V<Elipson> <Gamma Gamma>of 222Rn in a sample to be measured, wherein n<Gamma Gamma 1> is the counting rate of the third scaler during the process of measuring the sample to be measured; n is the background counting rateof the third scaler; V is the volume of the sample to be measured; and Epsilon <Gamma Gamma> is the detection efficiency of a coincidence channel. The novel system and method of measuring concentration of radon in water can quickly reduce the measurement background and can achieve the effect of quickly and accurately measuring the concentration of radon in water.

The subject system and method are generally directed to the user-friendly insertion of at least one device, and optionally chains of devices, into at least one pre-existing chain of interconnected devices within a graphical representation of a circuit design such as a circuit layout, circuit mask, or a schematic. The system and method provide for discerning the intended insertion points and performing remedial transformations of the devices within the chains to ensure compliance with both structural and operational requirements of the circuit design.

The invention relates to a single photon detector quantum efficiency absolute self-calibration method and dedicated apparatus therefore wherein, the parameter light beam is divided into two ways, then the time delay is introduced, making the twinning protons generated at spontaneously enter the single proton detector in sequence, then dividing the circuit after the detector into three ways, one of which enters directly into the counter to obtain the total counting ratio of the detected protons by the detector, the other two ways are led into the time lag corresponding to the optical path using the circuit method, and enter into the counter after the coincidence circuit, obtaining the coincidence counting rate of the proton pair arriving the detector in sequence, thus acquiring the quantum efficiency of the detector.

A particle detection system exhibits an increased ability to detect the presence of submicron diameter particles and to distinguish between noise and pulse output signals generated by small diameter particles on which a light beam is incident. This increased ability results from the incorporation of a light reflector, a pair of detector elements that detect correlated portions of the light beam that have been scattered in multiple directions, and a coincidence circuit that determines whether each detector element in the pair concurrently generates a pulse output signal exceeding a predetermined threshold. Sample particles are counted only when both detector elements concurrently detect scattered light components.

The invention provides a neutron detector, comprising a neutron absorbing crystal, a first photoelectric converter, a second photoelectric converter, a first pulse discrimination circuit, a second pulse discrimination circuit, a time-coincidence circuit and a counting system; wherein the first photoelectric converter and the second photoelectric converter are coupled with the neutron absorbing crystal; the first pulse discrimination circuit is used for carrying out amplitude discrimination on a first electric signal generated by the first photoelectric converter; the second pulse discrimination circuit is used for carrying out amplitude discrimination on a second electric signal generated by the second photoelectric converter; the time-coincidence circuit is used for determining whether time windows of the first electric signal and the second electric signal subjected to amplitude discrimination are the same, and if so, generating a determination effective signal; and the counting system is connected with the time coincidence circuit and triggered to count by the determination effective signal. According to the neutron detector provided by the invention, interference caused by gamma ray can be reduced even avoided.

The invention discloses a PET-CT (positron emission tomography-computed tomography) scanning device and a control method of the PET-CT scanning device. The PET-CT scanning device comprises a CT machine and a PET machine, wherein a luminous screen is arranged at a connecting part of the CT machine and the PET machine, the PET machine comprises a rebuilding computer, a coincidence circuit board and a PET control circuit board, the PET control circuit board is connected with the coincidence circuit board, the coincidence circuit board is connected with the rebuilding computer, and the PET control circuit board is connected with a driving circuit board of the luminous screen. The PET-CT scanning device and the control method of the PET-CT scanning device provided by the invention have the advantages that the body position change information of patients can be obtained through collecting light environment signal changes, so the scanning mages can be more accurately rebuilt.

The invention discloses a device and a method for realizing high sensitivity detection on radioactive gas nuclide activity and solves a problem that cosmic rays generate coincidence background counting in a coincidence measurement system. The device comprises an inflatable beta detector, a gamma detector, an anti cosmic ray detector set and a digital coincidence circuit, wherein the beta detector and the gamma detector are arranged in a lead shield, the beta detector is arranged on the gamma detector in a bottom down mode, the anti cosmic ray detector set is used for shielding coincidence signals generated by the cosmic rays in the beta detector and the gamma detector, the anti cosmic ray detector set comprises five anti cosmic ray detectors which are respectively arranged at a top portion and periphery of the lead shield, output signals of the anti cosmic ray detectors, output signals of the beta detector and output signals of the gamma detector are respectively transmitted to the digital coincidence circuit to acquire gamma detector original spectra, anti cosmic ray gamma spectra, beta-gamma coincidence spectra and anti cosmic ray beta-gamma coincidence spectra. The device is advantaged in that radioactive gas nuclide detection sensitivity can be greatly improved.

The invention discloses a display driver for at least driving scan lines in a display panel with multiple scan lines, multiple data lines and multiple pixels; it includes multiple scan drive units, multiple scan order registers, multiple Coincidence detection circuit. The plurality of scan driving units respectively drive each of the plurality of scan lines. The plurality of scan order registers are respectively connected to each of the plurality of coincidence detection circuits, and store scan order addresses indicating a scan order. A plurality of coincidence detection circuits are respectively connected to each scanning driving unit of the plurality of scanning driving units, and after comparing the scanning order addresses respectively stored in the plurality of scanning order registers with the scanning line address specified by the scanning control signal, The comparison result is output to each of the plurality of scan driving units.

The invention belongs to the technical field of anti-universe rays and concretely relates to an anti-universe ray system for internal exposure measurement and an anti-coincidence method. The anti-universe ray system for internal exposure measurement comprises an anti-coincidence detector disposed in a shielding chamber having a high-purity germanium detector and an electronics device arranged outside the shielding chamber and connected with the anti-coincidence detector and the high-purity germanium detector, wherein the electronics device has an anti-coincidence circuit and a multi-channel analyzer; the anti-coincidence detector can detect external cosmic ray signals; and the high-purity germanium detector can be applied to internal exposure measurement. Current internal exposure measurement has high background due to the effect by cosmic rays; by the use of the anti-universe ray system for internal exposure measurement and the anti-coincidence method, internal exposure monitoring background can be reduced and detection lower limit can be improved; acceptable daily intake amount of radioactive medicine by a testee during the internal exposure measurement can be reduced with the achievement of effective measuring effect; and radiation injury of the testee can be reduced.

The embodiment of the invention provides an artificial intelligence agent training system and an optimization design system and method for a passive circuit. A circuit model to be optimized and a required circuit model design index are input to enable an artificial intelligence agent to execute circuit optimization design processing by aiming at the circuit model according to the circuit model design index, a circuit optimization model which conforms to the circuit model design index is automatically generated, the sharing of different types of passive circuit design experiences can be realized, the reusability of circuit design is improved, and the method has the advantages of high design efficiency and low design cost.

The invention belongs to the technical field of radiation detection, and relates to a lamination scintillation type anti-compton gamma spectrometer. The lamination scintillation type anti-compton gamma spectrometer comprises a probe. The probe comprises a CeBr3 crystal scintillator, a BGO crystal scintillator, a photomultiplier and a charge-sensitive preamplifier and a shell packaging the parts. The CeBr3 crystal scintillator is used for measuring the gamma spectrum, and other external side parts are wrapped by the BGO crystal scintillator apart from the external side parts contacting the shell. The BGO crystal scintillator is connected with the photomultiplier and the charge-sensitive preamplifier and used for measuring the scintillation photons produced in the CeBr3 crystal scintillatorin case of the compton effect. With application of the lamination scintillation type anti-compton gamma spectrometer, the influence of the compton effect on measurement can be eliminated by only usingone instrument, and the coincidence circuit can be omitted and the instrument complexity and cost can be reduced so that the measurement system is enabled to be simpler, and the carrying convenienceand the use flexibility of the instrument can be increased.

An imaging device (1) includes a positron emission tomography (PET) scanner (10) including radiation detectors (12) and coincidence circuitry for detecting electron-positron annihilation events as 511keV gamma ray pairs defining lines of response (LORs) with each event having a detection time difference at between the 511 keV gamma rays of the pair. At least one processor (30) is programmed to reconstruct a dataset comprising detected electron-positron annihilation events acquired for a region of interest by the PET scanner to form a reconstructed PET image wherein the reconstruction includesTOF localization of the events along respective LORs using a TOF kernel having a location parameter dependent on At and a TOF kernel width or shape that varies over the region of interest. A displaydevice (34) is configured to display the reconstructed PET image.

The invention provides a positron emission tomography (PET) system and an image reconstruction method thereof. The PET system comprises a plurality of detector units arranged in the axial direction, and a plurality of coincidence logic circuits. Each detector unit is suitable for generating multiple single event counts; each coincidence logic circuit is connected to one or more corresponding detector units, wherein single event data generated by each detector unit is sent to the corresponding coincidence logic circuit, and the coincidence logic circuits generate coincidence counts of the detector units in parallel.

The invention relates a tracking method( / b) based on positioning monitoring system in the field of measuring technology (b), comprising: a capsule inside the body, a data recorder, a radioactive ray prober, and a data processor, wherein the capsule has three radioactive markers which emit positive electrons and have annihilation radiation with peripheral negative electrons. When positive and negative electrons disappear, two Gamma (r) photons of equal energy are emitted in opposite directions. As the radioactive prober detects the two Gamma (r) photons, the radioactive prober produces respectively two timing pulses, and then transmits the two timing pulses and coincidence circuits to the data processor after storing the two timing pulses and the coincidence circuits. The data processor conducts coincidence event selection between the two Gamma (r) photons by means of a tracking algorithm in accordance with coincidence event, calculates a focal aggregation position of true coincidence and lower coincidence circuits, and locates the position of the capsule inside the body. The tracking method of the invention locates can accurately the position of a capsule inside stomach and intestine based on radioactive markers.

The invention discloses a 4pibeta-gamma coincidence measurement device based on a multi-wire proportional chamber. A 4pibeta multi-wire proportional chamber detector comprises an upper cavity and a lower cavity; anode wires which are parallel to each other are arranged in the upper cavity and the lower cavity; detected gamma channel signals are mixed and processed through a gamma detection branchand then sent to a coincidence circuit and a counter; a beta channel signal detected by the 4pibeta multi-wire proportional chamber detector is processed by a beta detection branch; a coincidence channel signal is generated after the processed gamma channel signal and the processed beta channel signal are coincident, and the coincidence channel signal is sent to the counter; and the counter counts, and the processing unit acquires the radioactive activity value of the radioactive source. The invention further discloses a 4pibeta-gamma coincidence measurement method based on the multi-wire proportional chamber. The 4pibeta multi-wire proportional chamber detector which is designed independently is utilized, so that the source making difficulty of 4pibeta-gamma coincidence measurement of theradioactive activity absolute measurement method can be effectively reduced, and the radioactive activity value of a radioactive source such as a plane source can be directly measured.

The invention discloses a method and system for monitoring the radioactivity of main loop coolants in a nuclear power plant. The system comprises a gamma-ray detector, an energy spectrum analyzer anda computer. According to the system disclosed by the invention, through the gamma-ray detector based on a semiconductor detector, a scintillation detector and a coincidence circuit, on-line continuousgamma-energy spectrum measurement of the main loop coolants in the nuclear power plant is realized, further the analysis of the radioactivity of characteristic nuclides in the main loop coolants is completed, and the work that a worker samples for performing measurement and analysis in a laboratory can be replaced; workload of the worker is reduced, the exposure dose of the worker is reduced, andthe monitoring efficiency is improved; and in addition, through the scintillation detector and the coincidence circuit, the influence of Compton scattering rays and environmental background gamma-rays on low-energy nuclide recognition and a main nuclide activity analysis result in the main loop coolants can be effectively reduced, and the accuracy of the measuring result is improved.

The invention relates to a PET coincidence data volume control method and device, computer equipment and a storage medium. The method comprises the following steps: receiving delay coincidence data of a PET detector in a set time period, wherein the set time period comprises at least one moment; obtaining a delay count value corresponding to the delay coincidence data at the first moment according to the delay coincidence data, wherein the delay count value is used for representing the number of delay coincidence data in a first moment and a previous moment in the set time period; according to the delay count value and a preset delay count threshold value, carrying out packet loss processing on delay coincidence data at a first moment and a subsequent moment in the set time period, wherein the delay counting threshold value is related to the throughput of the data acquisition link for transmitting and receiving the instant coincidence data and the delay coincidence data. By adopting the method, the implementation cost of follow-up devices, workstations and the like in accordance with the circuit can be reduced.

The invention discloses a channel type radioactive detector with a low detection limit, which is used for a channel type radioactive monitoring system. The channel type radioactive detector comprises a shell, a shielding body arranged in the shell, a plastic scintillator, a first photomultiplier, a first preamplifier, a second photomultiplier, a second preamplifier, a signal processing and controlling unit. Two ends of the plastic scintillator are coupled with two photomultipliers through light guides to output two paths of pulse signals. The signal processing and controlling unit is internally provided with an adder circuit and an accordance circuit, which are used for adding two paths of the pulse signals to detect whether the pulse signals accord with requirements. In the invention, through a signal adding and accordance method and the shielding by using a lead shielding body, the cost can be effectively reduced, the noise is reduced, the signal to noise ratio is improved, the detection efficiency and the sensitivity are improved, and the energy detection lower limit is reduced, so that low-energy nuclides can be more effectively detected and measurement requirements are better met.

There are provided a gamma ray detecting apparatus, including: a secondary electron emitter causing a Compton scattering reaction with an incident gamma ray to emit secondary electrons in a progress direction of the gamma ray; a first radiation detector provided to be opposed to the secondary electron emitter with respect to an emission progress direction of the secondary electrons and detecting the position and transfer energy of the secondary electron; a second radiation detector provided to be opposed to the first radiation detector with respect to the emission progress direction of the secondary electron and detecting the position and the transfer energy of the secondary electron passing through the first radiation detector; a third radiation detector provided to be opposed to the second radiation detector with respect to the emission progress direction of the secondary electron and detecting residual energy of the secondary electron by absorbing the secondary electron passing through the second radiation detector; and a data processor having a coincidence circuit judging whether the secondary electrons simultaneously react in the first to third radiation detectors, and the data processor back traces trajectories of the secondary electrons detected by the first and second radiation detectors to detect the position of a ray source of the gamma ray, and a gamma ray detecting method.

The invention discloses an absolute measuring system and a method for radon concentration in water, wherein the measuring system comprises a first [gamma] detector, a first linear amplifier, a first single channel pulse amplitude analyzer, a first delay formation circuit, a first scalar connected in series, and a second [gamma] detector, a second linear amplifier, a second single channel pulse amplitude analyzer, a second delay formation circuit, a second scalar connected in series. The outputs of the first delay formation circuit and the second delay formation circuit are also connected to the input of a coincidence circuit, and the coincidence output of the coincidence circuit is connected to a third scalar. The measuring system also comprises a calculation module for calculating the activity concentration C222Rn of 222Rn in the sample to be tested. According to the absolute measuring system and the method for radon concentration in water, the radon concentration in the water can bemeasured accurately, in real time and conveniently without the need to scale the measuring system itself.

The invention relates to hydroacoustic domain, notably to methods and devices of active location. The method of controlling intercarrier frequency wave efficiency with parametric radiating antenna is based on placing electroacoustic transducer with piezoelement with given resonance frequency (f1+f2) / 2=f0 and pass band corresponding to intercarrier frequency wave diapason in locating area, feeding electric signals from radiating tract output to electroacoustic transducer piezoelement, forming in locating area spatial area of collinear distribution and non-linear interaction of intense ultrasound pimp waves, generation of intercarrier frequency wave with cyclic frequency Ω=2π|f1−f2|. New features are the following: multicomponent excitation signal if formed due to generating in radiating tract N oscillations with similar amplitude and with similar initial phase at the period of time t=0), with frequencies ωv, sequentially differing from each other by Ω=2πF_ and situated in pass band of piezoelement and coming from radiating tract output to piezoelement with resonance cyclic frequency ω0=2πf0 electric multicomponent signal of escitation, presented as sum of N oscillations and regulation of generation efficiency and adjusting of field parameters (N−1) of intercarrier frequency component wave with cyclical frequencies Ω, 2Ω, . . . , (N−1)Ω formed by parametric radiating antenna, implemented by switching off of antiphase switching on of given constituents set. The method is implemented due to the device that includes reference generator, delayed pulse-shaping circuit, (N−1) coincidence circuit, N frequency dividers, analog switch, adder, amplitude modulator, impulse generator, power amplifier, electroacoustic transducer, controlling and adjustment unit.

The invention relates to a quick positioning and measuring device for radioactive contamination on human body surface, which comprises a main crystal and a secondary crystal which is sheathed outsidethe main crystal; a light guide, with one end positioned at the end of the main crystal and the secondary crystal and the other end positioned at the end of the photomultiplier tube; a lead shieldinglayer which is sleeved outside the secondary crystal; a photomultiplier tube for converting the weak light signal sent from the light guide into an electrical signal; a magnetic shielding layer sleeved outside the photomultiplier tube; an outer cover is sleeved outside the lead shielding layer and the magnetic shielding layer; a amplifying circuit which is divided into two paths respectively sentto the main channel discriminator circuit and the peak detection circuit, and then accessed into the anti-coincidence circuit; the main crystal signal U2 output by the anti-coincidence circuit and thetotal count signal U1 output by the main channel discrimination circuit are respectively sent to the controller which determines the location of the radioactive contamination by calculation. The invention can rapidly position the radioactive contamination of the human body surface and prevent the interference, and the intelligent multi-function radioactive contamination instrument can be linked quickly and intelligently to realize quick elimination and improve the decontamination efficiency.

The invention discloses a gamma ray time measurement device and a method for manufacturing the detector thereof. The device comprises: a detector, a timing discrimination circuit, an amplification and shaping circuit, a single-channel pulse analyzer, a delay circuit, a time-amplitude conversion circuit, and a coincidence circuit and multi-channel analyzers. The present invention uses BaF2 crystal, POPOP, and silicone rubber as materials to make a composite scintillator with a special process, and process it into a honeycomb shape to form a detector, which can convert the fluorescence of 220nm wavelength emitted by BaF2 crystal into visible light with a wavelength of about 420nm, without A photomultiplier tube with a quartz window is needed, which greatly expands its application range; the structural design of the honeycomb shape increases the surface area of ​​the scintillator, so that part of the scintillation light can propagate in the air medium and reach the photodetector after refraction. The time of the photodetection device is shortened, so that the initial stage of the signal rises faster, which is beneficial to the timing of the timing discriminator, thereby improving the timing accuracy of the gamma ray time measuring device.

The invention discloses an over current detector, which adopts a first reverse gate and a second reverse gate; reverses a first digital signal and a second digital signal; adopts a compensation gold oxygen semiconductor crystal to receive the reversed signals and drive a load; when the current of the load is over, adopts a comparison circuit to detect the over current on the load to be compared with the reversed first and second digital signals; outputs a first electronic signal and a second electric signal to a first logic gate and a second logic gate; and provides the output signals of the logic gates to a protection circuit to control the current on the load, thereby preventing the whole circuit from being burnt and accident. The over current detector can detect over current accuratelyand effectively, and can be integrated with compensation gold oxygen semiconductor crystals, to save electricity and reduce circuit volume.

The invention discloses an absolute measuring system and a method for radon concentration in water, wherein the measuring system comprises a first [gamma] detector, a first linear amplifier, a first single channel pulse amplitude analyzer, a first delay formation circuit, a first scalar connected in series, and a second [gamma] detector, a second linear amplifier, a second single channel pulse amplitude analyzer, a second delay formation circuit, a second scalar connected in series. The outputs of the first delay formation circuit and the second delay formation circuit are also connected to the input of a coincidence circuit, and the coincidence output of the coincidence circuit is connected to a third scalar. The measuring system also comprises a calculation module for calculating the activity concentration C222Rn of 222Rn in the sample to be tested. According to the absolute measuring system and the method for radon concentration in water, the radon concentration in the water can bemeasured accurately, in real time and conveniently without the need to scale the measuring system itself.

There is provided a photon-counting x-ray detector system (200) comprising a plurality of photon-counting channels (220), and at least one anti-coincidence circuit (230), each of which is connected toleast two of the channels and configured to detect coincident events in the connected channels. The x-ray detector system (200) further comprises an anti-coincidence controller (240) configured to control the operation of said at least one anti-coincidence circuit based on photon count information by gradually adapting the operation of said at least one anti-coincidence circuit with increasing count rates, starting from a threshold count rate.