System and method for online monitoring of radiation status of radioactive material storage container

Abstract

The invention discloses an online monitoring system and method for the radiation status of a radioactive material storage container, and relates to the technical field of nuclear radiation monitoring. The online monitoring system for the radiation status of a radioactive material storage container comprises a detector, an FPGA chip, a communication module, a server and a user terminal; the detector is used to output a pixel matrix containing a radiation response signal and the position information of a target storage container; the FPGA chip is used to characterize the pixel matrix output by the detector as the radiation dose rate of the radioactive material; the server is used to store and display real-time radiation dose rate data and detector position data on the one hand, and to adjust the operating parameters of the FPGA chip on the other hand, and to send real-time radiation dose rate data to the outside on the other hand. The present invention adopts a non-destructive detection method to monitor the status of a radioactive material storage container online, and can inform the user through the user terminal at the first time of a nuclear leak.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear radiation monitoring, and in particular to an online monitoring system and method for the radiation status of a radioactive material storage container. Background Art

[0002] With the development of nuclear technology, nuclear radiation safety has gradually become an area of ​​concern. In industrial production, all kinds of radioactive materials should be strictly monitored during storage and transportation. Once a radioactive material leaks, it will have a serious impact on the natural environment and personal safety. Therefore, it is very necessary to monitor the state of radioactive materials in storage containers online so that they can be handled as soon as possible in case of radioactive material leakage, thereby minimizing the impact of nuclear leakage accidents on the environment and people.

[0003] The above-mentioned online monitoring process has the following difficulties: 1. Since radioactive material storage containers are usually stored and transported in a centralized manner, the number is often large. Most of the existing detection methods are unified detection of centralized storage areas. There is no equipment for individual monitoring of each storage container. Once a leakage accident occurs, it is impossible to quickly locate the target container where the leakage occurs. 2. In different storage containers, the activity (divided into three activity levels: high, medium, and low) and types of radioactive materials are not exactly the same. Matching detectors need to be set for radioactive materials of different activities and types, which puts high demands on the design of detectors. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide an online monitoring system and method for the radiation status of a radioactive material storage container, which is used to monitor the status of the radioactive material storage container online so as to deal with the radioactive material leakage as soon as possible, thereby minimizing the impact of nuclear leakage accidents on the environment and people.

[0005] The technical solution of the present invention is: an online monitoring system for the radiation status of a radioactive material storage container, comprising a detector, an FPGA chip, a communication module, a server and a user terminal;

[0006] The detector is fixedly mounted on the outer wall of the target storage container, and is used to output a pixel matrix including a radiation response signal and position information of the target storage container;

[0007] The FPGA chip is connected to the detector for communicating with the detector, and is used to represent the pixel matrix output by the detector as the radiation dose rate of the radioactive material;

[0008] The communication module is respectively connected to the detector and the FPGA chip for outputting radiation dose rate data and location information of the target storage container;

[0009] The server is in communication connection with the communication module, which is used to store and display real-time radiation dose rate data and detector position data on the one hand, and to adjust the operating parameters of the FPGA chip on the other hand, and to send real-time radiation dose rate data to the outside on the other hand;

[0010] The user terminal includes a PC and / or a smart phone. The user terminal is connected to the server via the Internet and is used to view real-time radiation dose rate data.

[0011] A further technical solution of the present invention is: the detector includes an active pixel sensor and a light-shielding film; a light-receiving surface is arranged on the outer surface of the active pixel sensor; the light-shielding film is covered and installed on the light-receiving surface of the active pixel sensor, and is used to prevent visible light from entering the light-receiving surface of the active pixel sensor.

[0012] A further technical solution of the present invention is: the detector includes an active pixel sensor, a gamma scintillation crystal and a shading film; a light receiving surface is arranged on the outer surface of the active pixel sensor; the gamma scintillation crystal is bonded to the light receiving surface of the active pixel sensor through a photoconductive material, and is used to convert gamma rays into light signals; the shading film is wrapped around the junction between the active pixel sensor and the gamma scintillation crystal, and is used to prevent visible light from entering the light receiving surface of the active pixel sensor.

[0013] A further technical solution of the present invention is: the detector includes an active pixel sensor, a neutron scintillation crystal and a light-shielding film; a light-receiving surface is arranged on the outer surface of the active pixel sensor; the neutron scintillation crystal is bonded to the light-receiving surface of the active pixel sensor through a photoconductive material, and is used to convert neutron radiation into a light signal; the light-shielding film is wrapped around the junction between the active pixel sensor and the neutron scintillation crystal, and is used to prevent visible light from entering the light-receiving surface of the active pixel sensor.

[0014] A further technical solution of the present invention is: it also includes a positioning module, the positioning module is fixedly installed on the detector and is communicatively connected with the communication module, and is used to obtain the location information of the detector. The positioning module is a GPS positioning module or a Beidou navigation positioning module.

[0015] The technical solution of the present invention is: a method for online monitoring of the radiation status of a radioactive material storage container, based on the above-mentioned online monitoring system for the radiation status of a radioactive material storage container; the following is divided into three cases to expand and explain the monitoring method;

[0016] Case 1: The gamma-ray dose rate on the detection surface is greater than 1mGy / h;

[0017] S01, acquisition pixel matrix:

[0018] a. A detector is fixedly mounted on the outer surface of a storage container to detect radiation conditions outside the storage container; the detector comprises an active pixel sensor and a light shielding film; the active pixel sensor acquires a light signal and outputs a pixel matrix including a radiation response signal; the light shielding film is used to prevent visible light from entering the active pixel sensor to eliminate interference of visible light on the radiation response signal collected by the active pixel sensor;

[0019] b. The pixel matrix acquired by the active pixel sensor is transmitted to the FPGA chip at a speed of 25 frames per second. The FPGA chip records the first 10 seconds of continuous frame pixel matrix as the first group of data and iterates every 10 seconds.

[0020] S02, performing matrix polarization processing on the pixel matrix:

[0021] a. Detect the background noise of the active pixel sensor to obtain the background noise threshold Th1, and set the threshold Th2 of the matrix secondaryization based on the background noise threshold Th1, so that Th2>Th1;

[0022] b. When the digital signal I (ij) ≤Th2, record I (ij) =0; when the digital signal I (ij) >Th2, record I (ij) =1; Based on this rule, the FPGA chip performs matrix binarization processing on the pixel array transmitted from the active pixel sensor to obtain matrix data containing only two numbers "0" and "1", so that the matrix data and the pixel array form a one-to-one correspondence;

[0023] c. Calculate the sum of the matrix data statistics of each set of 250 pixel matrices, marked as X i ;

[0024] S03, solve the radiation dose rate based on the high-dose radiation field characterization algorithm:

[0025] a. On the one hand, the radiation dose rate around the detector is detected by the detection equipment, and on the other hand, the sum of the matrix data statistics corresponding to the detection period is obtained. i , thus drawing the calibration curve of the detector, which represents the sum of the radiation dose rate and the matrix data statistics X i The functional correspondence between them is a high dose rate radiation field characterization algorithm;

[0026] b. Based on the high-dose radiation field characterization algorithm, the sum of the known calibration curve and matrix data statistics X i Under the premise of solving the radiation dose rate corresponding to each set of data;

[0027] S04, determining whether nuclear leakage occurs in the storage container:

[0028] a. The radiation dose rate corresponding to each set of data is sent to the server through the communication module. The server takes 100 consecutive sets of data to calculate the judgment reference value, among which the lowest value of the radiation dose rate is Z min The maximum radiation dose rate is Z max , if Z max With Z min The difference does not exceed Z min 5%, then the average value Z of the radiation dose rate corresponding to these 100 sets of data is calculated as the judgment reference value;

[0029] b. The server continuously iterates each group of data, records the radiation status of the storage container, and compares the radiation dose rate corresponding to the current group of data with the judgment reference value Z to determine whether a nuclear leak has occurred; the judgment rule is: if the radiation dose rate value of the current group of data exceeds the judgment reference value Z by 10%, it is determined that a nuclear leak has occurred; if the radiation dose rate value of the current group of data is less than or equal to 10% of the judgment reference value Z, it is determined that no nuclear leak has occurred.

[0030] Case 2: The gamma-ray dose rate on the detection surface is less than 1mGy / h;

[0031] S01, acquisition pixel matrix:

[0032] a. A detector is fixedly mounted on the outer surface of a storage container to detect radiation conditions outside the storage container; the detector comprises an active pixel sensor, a gamma scintillation crystal and a light shielding film; the gamma scintillation crystal is used to convert gamma rays into light signals, the active pixel sensor acquires the light signals and outputs a pixel matrix containing radiation response signals; the light shielding film is used to prevent visible light from entering the active pixel sensor to eliminate interference of visible light on the radiation response signals collected by the active pixel sensor;

[0033] b. The pixel matrix acquired by the active pixel sensor is transmitted to the FPGA chip at a speed of 25 frames per second. The FPGA chip records the first 10 seconds of continuous frame pixel matrix as the first group of data and iterates every 10 seconds.

[0034] S02, segment the pixel matrix into data:

[0035] a. The pixel matrix output by the active pixel sensor contains pixels with grayscale levels of 0 to 255, but only in the grayscale range of Th1 to Th3, there is a linear relationship between the radiation response signal and the radiation dose rate, where Th1 is the lower threshold value obtained by detecting the background noise of the active pixel sensor, and Th3 is the upper threshold value where there is a linear relationship between the radiation response signal and the radiation dose rate;

[0036] b. When the digital signal I (ij) ≤Th1, record I(ij) =0; when the digital signal I (ij) ≥Th3, record I (ij) =0; when Th1<I (ij) When <Th3, the sum of the grayscale value data statistics of each group of data, a total of 250 pixel matrices, is calculated and marked as S i ;

[0037] S03, solve the radiation dose rate based on the high-dose radiation field characterization algorithm:

[0038] a. On the one hand, the radiation dose rate around the detector is detected by the detection equipment, and on the other hand, the sum of the gray value data statistics corresponding to the detection period S is obtained. i , thus drawing the calibration curve of the detector, which represents the sum of the radiation dose rate and the statistical value of the matrix data and the statistical value of the gray value data S i The functional correspondence between them is a low-dose rate radiation field characterization algorithm;

[0039] b. Based on the low-dose radiation field characterization algorithm, the sum of the known calibration curve and grayscale data statistics S i Under the premise of solving the radiation dose rate corresponding to each set of data;

[0040] S04, determining whether nuclear leakage occurs in the storage container:

[0041] a. The radiation dose rate corresponding to each set of data is sent to the server through the communication module. The server takes 100 consecutive sets of data to calculate the judgment reference value, among which the lowest value of the radiation dose rate is Z min The maximum radiation dose rate is Z max , if Z max With Z min The difference does not exceed Z min 5%, then the average value Z of the radiation dose rate corresponding to these 100 sets of data is calculated as the judgment reference value;

[0042] b. The server continuously iterates each group of data, records the radiation status of the storage container, and compares the radiation dose rate corresponding to the current group of data with the judgment reference value Z to determine whether a nuclear leak has occurred; the judgment rule is: if the radiation dose rate value of the current group of data exceeds the judgment reference value Z by 10%, it is determined that a nuclear leak has occurred; if the radiation dose rate value of the current group of data is less than or equal to 10% of the judgment reference value Z, it is determined that no nuclear leak has occurred;

[0043] Case 3: The radiation type detected on the surface is neutron radiation:

[0044] S01, acquisition pixel matrix:

[0045] a. The detector is fixedly mounted on the outer surface of the storage container to detect the radiation situation outside the storage container; the detector includes an active pixel sensor, a neutron scintillation crystal and a light shielding film; the neutron scintillation crystal is used to convert neutron radiation into a light signal; the active pixel sensor acquires the light signal and outputs a pixel matrix containing a radiation response signal; the light shielding film is used to prevent visible light from entering the active pixel sensor to eliminate the interference of visible light on the radiation response signal collected by the active pixel sensor;

[0046] b. The pixel matrix acquired by the active pixel sensor is transmitted to the FPGA chip at a speed of 25 frames per second. The FPGA chip records the first 10 seconds of continuous frame pixel matrix as the first group of data and iterates every 10 seconds.

[0047] S02, segment the pixel matrix into data:

[0048] a. The pixel matrix output by the active pixel sensor contains pixels with grayscale levels of 0 to 255, but only in the grayscale range of Th1 to Th3, there is a linear relationship between the radiation response signal and the radiation dose rate, where Th1 is the lower threshold value obtained by detecting the background noise of the active pixel sensor, and Th3 is the upper threshold value where there is a linear relationship between the radiation response signal and the radiation dose rate;

[0049] b. When the digital signal I (ij) ≤Th1, record I (ij) =0; when the digital signal I (ij) ≥Th3, record I (ij) =0; when Th1<I (ij) When <Th3, the sum of the grayscale value data statistics of each group of data, a total of 250 pixel matrices, is calculated and marked as S i ;

[0050] S03, solve the radiation dose rate based on the neutron radiation field characterization algorithm:

[0051] a. On the one hand, the radiation dose rate around the detector is detected by the detection equipment, and on the other hand, the sum of the gray value data statistics corresponding to the detection period S is obtained. i , thus drawing the calibration curve of the detector, which represents the sum of the radiation dose rate and the statistical value of the matrix data and the statistical value of the gray value data S i The functional correspondence between them is the neutron radiation field characterization algorithm;

[0052] b. Based on the neutron radiation field characterization algorithm, the sum of the known calibration curve and gray value data statistics S i Under the premise of solving the radiation dose rate corresponding to each set of data;

[0053] S04, determining whether nuclear leakage occurs in the storage container:

[0054] a. The radiation dose rate corresponding to each set of data is sent to the server through the communication module. The server takes 100 consecutive sets of data to calculate the judgment reference value, among which the lowest value of the radiation dose rate is Z min The maximum radiation dose rate is Z max , if Z max With Z min The difference does not exceed Z min 5%, then the average value Z of the radiation dose rate corresponding to these 100 sets of data is calculated as the judgment reference value;

[0055] b. The server continuously iterates each group of data, records the radiation status of the storage container, and compares the radiation dose rate corresponding to the current group of data with the judgment reference value Z to determine whether a nuclear leak has occurred; the judgment rule is: if the radiation dose rate value of the current group of data exceeds the judgment reference value Z by 10%, it is determined that a nuclear leak has occurred; if the radiation dose rate value of the current group of data is less than or equal to 10% of the judgment reference value Z, it is determined that no nuclear leak has occurred.

[0056] A further technical solution of the present invention is: in step S01 of the above three situations, the radiation response signal is an output signal generated after the charges generated by ionized particles inside the active pixel sensor are collected by the charge collection area inside the active pixel sensor.

[0057] A further technical solution of the present invention is: in step S02 of the above three situations, the digital signal quantity refers to the grayscale value of each pixel in the pixel matrix.

[0058] A further technical solution of the present invention is: in step S04 of the above three situations, if the server determines that a nuclear leak has occurred, it immediately sends an alarm message containing a specific radiation dose rate and location information of a corresponding storage container to the radiation terminal.

[0059] Compared with the prior art, the present invention has the following advantages:

[0060] 1. It uses a non-destructive detection method to monitor the status of radioactive material storage containers online, and can inform users through user terminals as soon as a nuclear leak occurs, so that radioactive materials can be handled as soon as possible, thereby minimizing the impact of nuclear leaks on the environment and people.

[0061] 2. On the one hand, the active pixel sensor contained in the detector has a large number of independent pixel units, short integration time, high sampling rate, and can achieve fast and accurate detection; on the other hand, matching detectors are designed specifically for radioactive materials of different activities and types stored in storage containers, thereby broadening the detection range.

[0062] The present invention is further described below in conjunction with the figures and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 It is a schematic diagram of the communication connection relationship of each component in the present invention. DETAILED DESCRIPTION

[0064] Embodiment 1:

[0065] like Figure 1 As shown, the online monitoring system for the radiation status of a radioactive material storage container includes a detector 1, an FPGA chip 2, a communication module 3, a server 4 and a user terminal 5.

[0066] The detector 1 is fixedly mounted on the outer wall of the target storage container, and is used to output a pixel matrix including a radiation response signal and position information of the target storage container.

[0067] The FPGA chip 2 is in communication connection with the detector 1 and is used for representing the pixel matrix output by the detector 1 as the radiation dose rate of the radioactive material.

[0068] The communication module 3 is respectively connected to the detector 1 and the FPGA chip 2 for communicating with each other, and is used for outputting radiation dose rate data and location information of the target storage container.

[0069] The server 4 is connected to the communication module 3 through a router or a switch. On the one hand, it is used to store and display real-time radiation dose rate data and detector 1 position data, on the other hand, it is used to adjust the operating parameters of the FPGA chip 2, and on the other hand, it is used to send real-time radiation dose rate data to the outside.

[0070] The user terminal 5 includes a PC and / or a smart phone. The user terminal 5 is connected to the server 4 via the Internet and is used to view real-time radiation dose rate data.

[0071] Preferably, it also includes a positioning module 6, which is fixedly mounted on the detector 1 and is communicatively connected to the communication module 3, and is used to obtain the location information of the detector 1. The positioning module is a GPS positioning module or a Beidou navigation positioning module.

[0072] In this embodiment, the detector 1 includes an active pixel sensor and a light shielding film. A light receiving surface is provided on the outer surface of the active pixel sensor. The light shielding film is installed on the light receiving surface of the active pixel sensor to prevent visible light from entering the light receiving surface of the active pixel sensor.

[0073] Embodiment 2:

[0074] Compared with Example 1, the present embodiment differs only in that the detector 1 includes an active pixel sensor, a gamma scintillation crystal and a light shielding film. A light receiving surface is provided on the outer surface of the active pixel sensor. The gamma scintillation crystal is bonded to the light receiving surface of the active pixel sensor through a photoconductive material, and is used to convert gamma rays into light signals that can be sensed by the active pixel sensor. The light shielding film is provided around the junction of the active pixel sensor and the gamma scintillation crystal, and is used to prevent visible light from entering the light receiving surface of the active pixel sensor.

[0075] Embodiment 3:

[0076] Compared with Example 1, the present embodiment differs only in that the detector includes an active pixel sensor, a neutron scintillation crystal and a light shielding film. A light receiving surface is provided on the outer surface of the active pixel sensor. The neutron scintillation crystal is bonded to the light receiving surface of the active pixel sensor through a photoconductive material, and is used to convert neutron radiation into a light signal that can be detected by the active pixel sensor. The light shielding film is provided around the junction of the active pixel sensor and the neutron scintillation crystal, and is used to prevent visible light from entering the light receiving surface of the active pixel sensor.

[0077] Briefly describe the working principle of Example 1:

[0078] In Example 1, the online monitoring system for the radiation status of a radioactive material storage container is suitable for detecting a situation where the gamma-ray dose rate on the surface is greater than 1 mGy / h.

[0079] The online monitoring method is as follows:

[0080] S01, acquisition pixel matrix:

[0081] a. A detector is fixedly mounted on the outer surface of a storage container to detect radiation conditions outside the storage container; the detector comprises an active pixel sensor and a light shielding film; the active pixel sensor acquires a light signal and outputs a pixel matrix including a radiation response signal; the light shielding film is used to prevent visible light from entering the active pixel sensor to eliminate interference of visible light on the radiation response signal collected by the active pixel sensor;

[0082] b. The pixel matrix acquired by the active pixel sensor is transmitted to the FPGA chip at a speed of 25 frames per second. The FPGA chip records the first 10 seconds of continuous frame pixel matrix as the first group of data and iterates every 10 seconds.

[0083] In this step, the radiation response signal is an output signal generated after the charges generated by ionized particles in the active pixel sensor are collected by the charge collection area in the active pixel sensor.

[0084] S02, performing matrix polarization processing on the pixel matrix:

[0085] a. Detect the background noise of the active pixel sensor to obtain the background noise threshold Th1, and set the threshold Th2 of the matrix secondaryization based on the background noise threshold Th1, so that Th2>Th1;

[0086] b. When the digital signal I (ij) ≤Th2, record I (ij) =0; when the digital signal I (ij) >Th2, record I (ij) =1; Based on this rule, the FPGA chip performs matrix binarization processing on the pixel array transmitted from the active pixel sensor to obtain matrix data containing only two numbers "0" and "1", so that the matrix data and the pixel array form a one-to-one correspondence;

[0087] c. Calculate the sum of the matrix data statistics of each set of 250 pixel matrices, marked as X i .

[0088] In this step, the digital signal refers to the grayscale value of each pixel in the pixel matrix.

[0089] S03, solve the radiation dose rate based on the high-dose radiation field characterization algorithm:

[0090] a. On the one hand, the radiation dose rate around the detector is detected by the detection equipment, and on the other hand, the sum of the matrix data statistics corresponding to the detection period is obtained. i , thus drawing the calibration curve of the detector, which represents the sum of the radiation dose rate and the matrix data statistics X i The functional correspondence between them is a high dose rate radiation field characterization algorithm;

[0091] b. Based on the high-dose radiation field characterization algorithm, the sum of the known calibration curve and matrix data statistics X i Under the premise of , solve the radiation dose rate corresponding to each set of data.

[0092] S04, determining whether nuclear leakage occurs in the storage container:

[0093] a. The radiation dose rate corresponding to each set of data is sent to the server through the communication module. The server takes 100 consecutive sets of data to calculate the judgment reference value, among which the lowest value of the radiation dose rate is Z min The maximum radiation dose rate is Z max , if Z max With Z min The difference does not exceed Z min 5%, then the average value Z of the radiation dose rate corresponding to these 100 sets of data is calculated as the judgment reference value;

[0094] b. The server continuously iterates each group of data, records the radiation status of the storage container, and compares the radiation dose rate corresponding to the current group of data with the judgment reference value Z to determine whether a nuclear leak has occurred; the judgment rule is: if the radiation dose rate value of the current group of data exceeds the judgment reference value Z by 10%, it is determined that a nuclear leak has occurred; if the radiation dose rate value of the current group of data is less than or equal to 10% of the judgment reference value Z, it is determined that no nuclear leak has occurred.

[0095] Briefly describe the working principle of Example 2:

[0096] In Example 2, the online monitoring system for the radiation status of a radioactive material storage container is suitable for detecting a situation where the gamma-ray dose rate on the surface is less than 1 mGy / h.

[0097] The online monitoring method is as follows:

[0098] S01, acquisition pixel matrix:

[0099] a. A detector is fixedly mounted on the outer surface of a storage container to detect radiation conditions outside the storage container; the detector comprises an active pixel sensor, a gamma scintillation crystal and a light shielding film; the gamma scintillation crystal is used to convert gamma rays into light signals, the active pixel sensor acquires the light signals and outputs a pixel matrix containing radiation response signals; the light shielding film is used to prevent visible light from entering the active pixel sensor to eliminate interference of visible light on the radiation response signals collected by the active pixel sensor;

[0100] b. The pixel matrix acquired by the active pixel sensor is transmitted to the FPGA chip at a speed of 25 frames per second. The FPGA chip records the first 10 seconds of continuous frame pixel matrix as the first group of data and iterates every 10 seconds.

[0101] S02, segment the pixel matrix into data:

[0102] a. The pixel matrix output by the active pixel sensor contains pixels with grayscale levels of 0 to 255, but only in the grayscale range of Th1 to Th3, there is a linear relationship between the radiation response signal and the radiation dose rate, where Th1 is the lower threshold value obtained by detecting the background noise of the active pixel sensor, and Th3 is the upper threshold value where there is a linear relationship between the radiation response signal and the radiation dose rate;

[0103] b. When the digital signal I (ij) ≤Th1, record I (ij) =0; when the digital signal I (ij) ≥Th3, record I (ij) =0; when Th1<I (ij) When <Th3, the sum of the grayscale value data statistics of each group of data, a total of 250 pixel matrices, is calculated and marked as S i .

[0104] S03, solve the radiation dose rate based on the high-dose radiation field characterization algorithm:

[0105] a. On the one hand, the radiation dose rate around the detector is detected by the detection equipment, and on the other hand, the sum of the gray value data statistics corresponding to the detection period S is obtained. i , thus drawing the calibration curve of the detector, which represents the sum of the radiation dose rate and the statistical value of the matrix data and the statistical value of the gray value data S i The functional correspondence between them is a low-dose rate radiation field characterization algorithm;

[0106] b. Based on the low-dose radiation field characterization algorithm, the sum of the known calibration curve and grayscale data statistics S i Under the premise of , solve the radiation dose rate corresponding to each set of data.

[0107] S04, determining whether nuclear leakage occurs in the storage container:

[0108] a. The radiation dose rate corresponding to each set of data is sent to the server through the communication module. The server takes 100 consecutive sets of data to calculate the judgment reference value, among which the lowest value of the radiation dose rate is Z min The maximum radiation dose rate is Z max , if Z max With Z min The difference does not exceed Z min 5%, then the average value Z of the radiation dose rate corresponding to these 100 sets of data is calculated as the judgment reference value;

[0109] b. The server continuously iterates each group of data, records the radiation status of the storage container, and compares the radiation dose rate corresponding to the current group of data with the judgment reference value Z to determine whether a nuclear leak has occurred; the judgment rule is: if the radiation dose rate value of the current group of data exceeds the judgment reference value Z by 10%, it is determined that a nuclear leak has occurred; if the radiation dose rate value of the current group of data is less than or equal to 10% of the judgment reference value Z, it is determined that no nuclear leak has occurred.

[0110] Briefly describe the working principle of Example 3:

[0111] In Example 3, the online monitoring system for the radiation status of a radioactive material storage container is suitable for detecting a case where the type of radiation on the surface is neutron radiation.

[0112] S01, acquisition pixel matrix:

[0113] b. The detector is fixedly mounted on the outer surface of the storage container to detect the radiation situation outside the storage container; the detector includes an active pixel sensor, a neutron scintillation crystal and a light shielding film; the neutron scintillation crystal is used to convert neutron radiation into a light signal; the active pixel sensor acquires the light signal and outputs a pixel matrix containing a radiation response signal; the light shielding film is used to prevent visible light from entering the active pixel sensor to eliminate the interference of visible light on the radiation response signal collected by the active pixel sensor;

[0114] b. The pixel matrix acquired by the active pixel sensor is transmitted to the FPGA chip at a speed of 25 frames per second. The FPGA chip records the first 10 seconds of continuous frame pixel matrix as the first group of data and iterates every 10 seconds.

[0115] S02, segment the pixel matrix into data:

[0116] a. The pixel matrix output by the active pixel sensor contains pixels with grayscale levels of 0 to 255, but only in the grayscale range of Th1 to Th3, there is a linear relationship between the radiation response signal and the radiation dose rate, where Th1 is the lower threshold value obtained by detecting the background noise of the active pixel sensor, and Th3 is the upper threshold value where there is a linear relationship between the radiation response signal and the radiation dose rate;

[0117] b. When the digital signal I (ij) ≤Th1, record I (ij) =0; when the digital signal I (ij) ≥Th3, record I (ij) =0; when Th1<I (ij) When <Th3, the sum of the grayscale value data statistics of each group of data, a total of 250 pixel matrices, is calculated and marked as S i .

[0118] S03, solve the radiation dose rate based on the neutron radiation field characterization algorithm:

[0119] a. On the one hand, the radiation dose rate around the detector is detected by the detection equipment, and on the other hand, the sum of the gray value data statistics corresponding to the detection period S is obtained. i , thus drawing the calibration curve of the detector, which represents the sum of the radiation dose rate and the statistical value of the matrix data and the statistical value of the gray value data S i The functional correspondence between them is the neutron radiation field characterization algorithm;

[0120] b. Based on the neutron radiation field characterization algorithm, the sum of the known calibration curve and gray value data statistics S i Under the premise of , solve the radiation dose rate corresponding to each set of data.

[0121] S04, determining whether nuclear leakage occurs in the storage container:

[0122] a. The radiation dose rate corresponding to each set of data is sent to the server through the communication module. The server takes 100 consecutive sets of data to calculate the judgment reference value, among which the lowest value of the radiation dose rate is Z min The maximum radiation dose rate is Z max , if Z max With Z min The difference does not exceed Z min 5%, then the average value Z of the radiation dose rate corresponding to these 100 sets of data is calculated as the judgment reference value;

[0123] b. The server continuously iterates each group of data, records the radiation status of the storage container, and compares the radiation dose rate corresponding to the current group of data with the judgment reference value Z to determine whether a nuclear leak has occurred; the judgment rule is: if the radiation dose rate value of the current group of data exceeds the judgment reference value Z by 10%, it is determined that a nuclear leak has occurred; if the radiation dose rate value of the current group of data is less than or equal to 10% of the judgment reference value Z, it is determined that no nuclear leak has occurred.

[0124] In this step, if the server determines that a nuclear leak has occurred, it immediately sends an alarm message containing a specific radiation dose rate and location information of a corresponding storage container to the radiation terminal.

Claims

1. A method for online monitoring of the radiation status of a radioactive material storage container, based on an online monitoring system for the radiation status of a radioactive material storage container. Its characteristics are: Online monitoring system for radiation status of radioactive material storage containers, including detectors, FPGA chips, communication modules, servers, user terminals and positioning modules; The detector is fixedly mounted on the outer wall of the target storage container, and is used to output a pixel matrix including a radiation response signal and position information of the target storage container; The FPGA chip is connected to the detector for communicating with the detector, and is used to represent the pixel matrix output by the detector as the radiation dose rate of the radioactive material; The communication module is respectively connected to the detector and the FPGA chip for outputting radiation dose rate data and location information of the target storage container; The server is in communication connection with the communication module, which is used to store and display real-time radiation dose rate data and detector position data on the one hand, and to adjust the operating parameters of the FPGA chip on the other hand, and to send real-time radiation dose rate data to the outside on the other hand; The user terminal includes a PC and / or a smart phone, and the user terminal is connected to the server via the Internet, and is used to view real-time radiation dose rate data; The positioning module is fixedly installed on the detector and is connected to the communication module for communication. It is used to obtain the location information of the detector. The positioning module is a GPS positioning module or a Beidou navigation positioning module; The following three situations are used to explain the monitoring method; Case 1: The gamma-ray dose rate on the detection surface is greater than 1mGy / h; S01, acquisition pixel matrix: a. A detector is fixedly mounted on the outer surface of a storage container to detect radiation conditions outside the storage container; the detector comprises an active pixel sensor and a light shielding film; the active pixel sensor acquires a light signal and outputs a pixel matrix including a radiation response signal; the light shielding film is used to prevent visible light from entering the active pixel sensor to eliminate interference of visible light on the radiation response signal collected by the active pixel sensor; b. The pixel matrix acquired by the active pixel sensor is transmitted to the FPGA chip at a speed of 25 frames per second. The FPGA chip records the first 10 seconds of continuous frame pixel matrix as the first group of data and iterates every 10 seconds. S02, performing matrix polarization processing on the pixel matrix: a. Detect the background noise of the active pixel sensor to obtain the background noise threshold Th1, and set the threshold Th2 of the matrix secondaryization based on the background noise threshold Th1, so that Th2>Th1; b. When the digital signal I (ij) ≤Th2, record I (ij) =0; when the digital signal I (ij) >Th2, record I (ij) =1; Based on this rule, the FPGA chip performs matrix binarization processing on the pixel array transmitted from the active pixel sensor to obtain matrix data containing only two numbers "0" and "1", so that the matrix data and the pixel array form a one-to-one correspondence; c. Calculate the sum of the matrix data statistics of each set of 250 pixel matrices, marked as X i ; S03, solve the radiation dose rate based on the high-dose radiation field characterization algorithm: a. On the one hand, the radiation dose rate around the detector is detected by the detection equipment, and on the other hand, the sum of the matrix data statistics corresponding to the detection period is obtained. i , thus drawing the calibration curve of the detector, which represents the sum of the radiation dose rate and the matrix data statistics X i The functional correspondence between them is a high dose rate radiation field characterization algorithm; b. Based on the high-dose radiation field characterization algorithm, the sum of the known calibration curve and matrix data statistics X i Under the premise of solving the radiation dose rate corresponding to each set of data; S04, determining whether nuclear leakage occurs in the storage container: a. The radiation dose rate corresponding to each set of data is sent to the server through the communication module. The server takes 100 consecutive sets of data to calculate the judgment reference value, among which the lowest value of the radiation dose rate is Z min The maximum radiation dose rate is Z max , if Z max With Z min The difference does not exceed Z min 5%, then the average value Z of the radiation dose rate corresponding to these 100 sets of data is calculated as the judgment reference value; b. The server continuously iterates each group of data, records the radiation status of the storage container, and compares the radiation dose rate corresponding to the current group of data with the judgment reference value Z to determine whether a nuclear leak has occurred; the judgment rule is: if the radiation dose rate value of the current group of data exceeds the judgment reference value Z by 10%, it is determined that a nuclear leak has occurred; if the radiation dose rate value of the current group of data is less than or equal to 10% of the judgment reference value Z, it is determined that no nuclear leak has occurred; Case 2: The gamma-ray dose rate on the detection surface is less than 1mGy / h; S01, acquisition pixel matrix: a. A detector is fixedly mounted on the outer surface of a storage container to detect radiation conditions outside the storage container; the detector comprises an active pixel sensor, a gamma scintillation crystal and a light shielding film; the gamma scintillation crystal is used to convert gamma rays into light signals, the active pixel sensor acquires the light signals and outputs a pixel matrix containing radiation response signals; the light shielding film is used to prevent visible light from entering the active pixel sensor to eliminate interference of visible light on the radiation response signals collected by the active pixel sensor; b. The pixel matrix acquired by the active pixel sensor is transmitted to the FPGA chip at a speed of 25 frames per second. The FPGA chip records the first 10 seconds of continuous frame pixel matrix as the first group of data and iterates every 10 seconds. S02, segment the pixel matrix into data: a. The pixel matrix output by the active pixel sensor contains pixels with grayscale levels of 0 to 255, but only in the grayscale range of Th1 to Th3, there is a linear relationship between the radiation response signal and the radiation dose rate, where Th1 is the lower threshold value obtained by detecting the background noise of the active pixel sensor, and Th3 is the upper threshold value where there is a linear relationship between the radiation response signal and the radiation dose rate; b. When the digital signal I (ij) ≤Th1, record I (ij) =0; when the digital signal I (ij) ≥Th3, record I (ij) =0; when Th1<I (ij) When <Th3, the sum of the grayscale value data statistics of each group of data, a total of 250 pixel matrices, is calculated and marked as S i ; S03, solve the radiation dose rate based on the high-dose radiation field characterization algorithm: a. On the one hand, the radiation dose rate around the detector is detected by the detection equipment, and on the other hand, the sum of the gray value data statistics corresponding to the detection period S is obtained. i , thus drawing the calibration curve of the detector, which represents the sum of the radiation dose rate and the statistical value of the matrix data and the statistical value of the gray value data S i The functional correspondence between them is a low-dose rate radiation field characterization algorithm; b. Based on the low-dose radiation field characterization algorithm, the sum of the known calibration curve and grayscale data statistics S i Under the premise of solving the radiation dose rate corresponding to each set of data; S04, determining whether nuclear leakage occurs in the storage container: a. The radiation dose rate corresponding to each set of data is sent to the server through the communication module. The server takes 100 consecutive sets of data to calculate the judgment reference value, among which the lowest value of the radiation dose rate is Z min The maximum radiation dose rate is Z max , if Z max With Z min The difference does not exceed Z min 5%, then the average value Z of the radiation dose rate corresponding to these 100 sets of data is calculated as the judgment reference value; b. The server continuously iterates each group of data, records the radiation status of the storage container, and compares the radiation dose rate corresponding to the current group of data with the judgment reference value Z to determine whether a nuclear leak has occurred; the judgment rule is: if the radiation dose rate value of the current group of data exceeds the judgment reference value Z by 10%, it is determined that a nuclear leak has occurred; if the radiation dose rate value of the current group of data is less than or equal to 10% of the judgment reference value Z, it is determined that no nuclear leak has occurred; Case 3: The radiation type detected on the surface is neutron radiation: S01, acquisition pixel matrix: c. The detector is fixedly mounted on the outer surface of the storage container to detect the radiation situation outside the storage container; the detector includes an active pixel sensor, a neutron scintillation crystal and a light shielding film; the neutron scintillation crystal is used to convert neutron radiation into a light signal; the active pixel sensor acquires the light signal and outputs a pixel matrix containing a radiation response signal; the light shielding film is used to prevent visible light from entering the active pixel sensor to eliminate the interference of visible light on the radiation response signal collected by the active pixel sensor; b. The pixel matrix acquired by the active pixel sensor is transmitted to the FPGA chip at a speed of 25 frames per second. The FPGA chip records the first 10 seconds of continuous frame pixel matrix as the first group of data and iterates every 10 seconds. S02, segment the pixel matrix into data: a. The pixel matrix output by the active pixel sensor contains pixels with grayscale levels of 0 to 255, but only in the grayscale range of Th1 to Th3, there is a linear relationship between the radiation response signal and the radiation dose rate, where Th1 is the lower threshold value obtained by detecting the background noise of the active pixel sensor, and Th3 is the upper threshold value where there is a linear relationship between the radiation response signal and the radiation dose rate; b. When the digital signal I (ij) ≤Th1, record I (ij) =0; when the digital signal I (ij) ≥Th3, record I (ij) =0; when Th1<I (ij) When <Th3, the sum of the grayscale value data statistics of each group of data, a total of 250 pixel matrices, is calculated and marked as S i ; S03, solve the radiation dose rate based on the neutron radiation field characterization algorithm: a. On the one hand, the radiation dose rate around the detector is detected by the detection equipment, and on the other hand, the sum of the gray value data statistics corresponding to the detection period S is obtained. i , thus drawing the calibration curve of the detector, which represents the sum of the radiation dose rate and the statistical value of the matrix data and the statistical value of the gray value data S i The functional correspondence between them is the neutron radiation field characterization algorithm; b. Based on the neutron radiation field characterization algorithm, the sum of the known calibration curve and gray value data statistics S i Under the premise of solving the radiation dose rate corresponding to each set of data; S04, determining whether nuclear leakage occurs in the storage container: a. The radiation dose rate corresponding to each set of data is sent to the server through the communication module. The server takes 100 consecutive sets of data to calculate the judgment reference value, among which the lowest value of the radiation dose rate is Z min The maximum radiation dose rate is Z max , if Z max With Z min The difference does not exceed Z min 5%, then the average value Z of the radiation dose rate corresponding to these 100 sets of data is calculated as the judgment reference value; b. The server continuously iterates each group of data, records the radiation status of the storage container, and compares the radiation dose rate corresponding to the current group of data with the judgment reference value Z to determine whether a nuclear leak has occurred; the judgment rule is: if the radiation dose rate value of the current group of data exceeds the judgment reference value Z by 10%, it is determined that a nuclear leak has occurred; if the radiation dose rate value of the current group of data is less than or equal to 10% of the judgment reference value Z, it is determined that no nuclear leak has occurred.

2. The method for online monitoring of the radiation status of a radioactive material storage container according to claim 1, characterized in that: In step S01 of the above three situations, the radiation response signal is an output signal generated after the charges generated by ionization of ionized particles inside the active pixel sensor are collected by the charge collection area inside the active pixel sensor.

3. The method for online monitoring of the radiation status of a radioactive material storage container according to claim 2, characterized in that: In step S02 of the above three situations, the digital signal quantity refers to the grayscale value of each pixel in the pixel matrix.

4. The method for online monitoring of the radiation status of a radioactive material storage container as claimed in claim 3, characterized in that: In step S04 of the above three situations, if the server determines that a nuclear leak has occurred, it immediately sends an alarm message containing a specific radiation dose rate and location information of a corresponding storage container to the radiation terminal.

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