Radioactivity monitoring management system for inspection equipment

Abstract

The invention relates to the field of environmental monitoring, and discloses a radioactivity monitoring management system for inspection equipment, and the method comprises the steps: recognizing a radioactive material of the radioactive equipment, and constructing a remote monitoring module of the radioactive equipment; constructing a detector response matrix of the remote monitoring module, constructing a nuclide identification algorithm of the radioactive equipment, and determining a radioactive source gamma-ray energy spectrum of the radioactive equipment; analyzing the radioactive characteristic peak energy and the radioactive characteristic peak area of the radioactive equipment, identifying the radionuclide of the radioactive equipment, and calculating the radionuclide activity of the radioactive equipment; determining the decay type and the half-life period of the radionuclide, and calculating the exposure dose of the radioactive equipment; and constructing an early warning mechanism of the radioactive equipment, and constructing a radioactivity monitoring management system of the radioactive equipment. According to the invention, the accurate monitoring effect of equipment radioactivity can be improved.

Description

Technical Field

[0001] The invention relates to the field of environmental monitoring, and in particular to a radioactivity monitoring and management system for inspection equipment. Background Art

[0002] Checking equipment for radioactivity means testing the equipment for radioactivity to determine whether it contains radioactive substances or is contaminated by radioactivity. Checking equipment for radioactivity can prevent radioactive substances from leaking into the environment, protecting the ecological environment and public health.

[0003] At present, the radioactivity monitoring and management of equipment mainly uses portable or fixed surface contamination monitoring equipment to detect the deposition of radioactive substances on the equipment surface. This method can only detect specific types of radiation (such as gamma rays and beta particles), but cannot detect other types of radiation, which seriously affects the precise analysis of energy spectra and leads to inaccurate equipment radioactivity monitoring. Summary of the invention

[0004] The present invention provides a radioactivity monitoring and management system for inspection equipment, the main purpose of which is to improve the energy utilization rate of an air-conditioning system.

[0005] To achieve the above-mentioned purpose, the present invention provides a radioactive monitoring and management system for inspection equipment, comprising: a remote monitoring module, an energy spectrum analysis module, a nuclide identification module, an exposure dose analysis module and a monitoring and management module;

[0006] The remote monitoring module is used to obtain equipment data of the radioactive equipment, identify the radioactive material of the radioactive equipment according to the equipment data, determine the material type and material quantity of the radioactive material, build a remote monitoring module for the radioactive equipment according to the material type and the material quantity, and use the remote monitoring module to monitor the radioactive equipment to obtain equipment monitoring data;

[0007] The energy spectrum analysis module is used to construct the detector response matrix of the remote monitoring module, construct the nuclide identification algorithm of the radioactive equipment according to the detector response matrix, and determine the gamma energy spectrum of the radioactive source of the radioactive equipment according to the material type, the material quantity and the equipment monitoring data;

[0008] The nuclide identification module is used to analyze the radioactive characteristic peak energy and radioactive characteristic peak area of ​​the radioactive device according to the detector response matrix and the gamma energy spectrum of the radiation source using the nuclide identification algorithm, identify the radioactive nuclide of the radioactive device according to the radioactive characteristic peak energy, and calculate the nuclide activity of the radioactive device according to the radioactive characteristic peak area;

[0009] The exposure dose analysis module is used to determine the decay type and half-life of the radionuclide according to the nuclide activity, construct a radioactive decay curve of the radionuclide according to the decay type and the half-life, and calculate the exposure dose of the radioactive device according to the radioactive decay curve;

[0010] The monitoring and management module is used to construct an early warning mechanism for the radioactive equipment according to the nuclide activity and the exposure dose, and to construct a radioactive monitoring and management system for the radioactive equipment according to the early warning mechanism.

[0011] Optionally, constructing a remote monitoring module for the radioactive equipment according to the material type and the material quantity includes:

[0012] Determine the monitoring requirements of the radioactive equipment according to the type of the material and the quantity of the material, and analyze the radioactive risk of the radioactive equipment;

[0013] Determining the detector of the radioactive equipment according to the monitoring requirements and the radioactive risks;

[0014] Constructing a data acquisition unit, a communication unit and a power management unit of the detector;

[0015] Constructing a monitoring network for the radioactive equipment, wherein the monitoring network includes: equipment layout, data flow and communication protocol;

[0016] Based on the monitoring network, the data acquisition unit, the communication unit, the power management unit and the detector are integrated into a remote monitoring module.

[0017] Optionally, it is characterized in that the detector response matrix of the remote monitoring module is constructed, including:

[0018] Determine the monitoring energy range of the detector corresponding to the remote monitoring module, and obtain a known standard source within the monitoring energy range;

[0019] Using the detector to monitor the known standard source to obtain known standard source data;

[0020] Performing energy spectrum analysis on the known standard source data to obtain an energy spectrum analysis result, and identifying the energy full energy peak of the known standard source according to the energy spectrum analysis result;

[0021] Determining the total energy peak parameters of the energy total energy peak, and fitting the energy calibration results of the total energy peak parameters;

[0022] According to the energy calibration results, respectively constructing the energy response matrix, the nuclide response matrix and the mixed response matrix of the remote monitoring module;

[0023] Based on the energy response matrix, the nuclide response matrix and the mixed response matrix, a detector response matrix of the remote monitoring module is determined.

[0024] Optionally, it is characterized in that constructing a nuclide identification algorithm for the radioactive device according to the detector response matrix comprises:

[0025] monitoring the measured gamma spectrum of the radioactive equipment;

[0026] Constructing an initial algorithm for the radioactive device, and calculating the original ray spectrum of the radioactive device using the initial algorithm according to the measured gamma energy spectrum and the detector response matrix;

[0027] Based on the original ray spectrum, construct an iterative algorithm of the initial algorithm;

[0028] Determining a termination judgment condition of the iterative algorithm according to the preset iterative residual accuracy;

[0029] According to the initial algorithm, the iterative algorithm and the termination judgment condition, the nuclide identification algorithm of the radioactive equipment is integrated.

[0030] Optionally, it is characterized in that the step of analyzing the radioactive characteristic peak energy and the radioactive characteristic peak area of ​​the radioactive equipment by using the nuclide identification algorithm according to the detector response matrix and the gamma spectrum of the radiation source comprises:

[0031] Constructing a response matrix-gamma spectrum of the radioactive device according to the detector response matrix and the radiation source gamma spectrum;

[0032] Determining peak position energy data and peak area of ​​the response matrix-gamma spectrum;

[0033] Based on the peak energy data and the peak area, the response matrix-gamma spectrum is reconstructed using the nuclide identification algorithm to obtain an identification algorithm-gamma spectrum;

[0034] Detecting background radiation of the recognition algorithm-gamma energy spectrum, and performing background subtraction on the recognition algorithm-gamma energy spectrum according to the background radiation to obtain a subtracted gamma energy spectrum;

[0035] The characteristic peak of the subtracted gamma spectrum is identified, and the radioactive characteristic peak energy and the radioactive characteristic peak area of ​​the characteristic peak are determined.

[0036] Optionally, it is characterized in that the calculating the nuclide activity of the radioactive device according to the radioactive characteristic peak area comprises:

[0037] Calculate the characteristic peak net area of ​​the radioactive characteristic peak area;

[0038] Determining the detection efficiency and detection time of the remote monitoring module corresponding to the radioactive equipment;

[0039] Analyzing the energy gamma-ray branching ratio of the characteristic peak corresponding to the characteristic peak area of ​​the radioactive characteristic peak;

[0040] According to the characteristic peak net area, the detection efficiency, the detection time and the energy gamma ray branching ratio.

[0041] Optionally, it is characterized in that the determining the decay type and half-life of the radioactive nuclide according to the nuclide activity comprises:

[0042] determining the radiation energy of the radionuclide;

[0043] Inferring the decay type of the radioactive nuclide according to the radiation energy, wherein the decay type includes: alpha decay, beta decay and gamma decay;

[0044] Determining the initial activity of the radionuclide and determining the measurement time of the activity of the radionuclide;

[0045] Measuring the final activity of the radionuclide according to the measurement time;

[0046] According to the initial activity, the measurement time and the final activity.

[0047] Optionally, it is characterized in that constructing the radioactive decay curve of the radionuclide according to the decay type and the half-life includes:

[0048] Determining a curve construction requirement for the radionuclide, and determining a time range for the radionuclide according to the curve construction requirement;

[0049] Based on the time frame stated;

[0050] The radioactive decay curve of the radioactive nuclide is fitted according to the change in the activity of the nuclide.

[0051] Optionally, it is characterized in that the calculating the exposure dose of the radioactive device according to the radioactive decay curve comprises:

[0052] Acquiring an exposure position, and measuring a distance between the exposure position and the radioactive device;

[0053] Determining the current nuclide activity of the radioactive device according to the radioactive decay curve;

[0054] analyzing a dose rate constant of the radioactive device;

[0055] According to the dose rate constant, the distance and the current nuclide activity.

[0056] A method for monitoring and managing radioactivity of inspection equipment, characterized in that the method comprises:

[0057] Acquire equipment data of a radioactive device, identify the radioactive material of the radioactive device according to the equipment data, determine the material type and material quantity of the radioactive material, construct a remote monitoring module for the radioactive device according to the material type and the material quantity, monitor the radioactive device using the remote monitoring module, and obtain equipment monitoring data;

[0058] Constructing a detector response matrix of the remote monitoring module, constructing a nuclide identification algorithm for the radioactive device based on the detector response matrix, and determining a gamma energy spectrum of the radioactive source of the radioactive device based on the material type, the material quantity and the device monitoring data;

[0059] According to the detector response matrix and the gamma energy spectrum of the radiation source, the radioactive characteristic peak energy and the radioactive characteristic peak area of ​​the radioactive device are analyzed by using the radionuclide identification algorithm, the radioactive nuclide of the radioactive device is identified according to the radioactive characteristic peak energy, and the nuclide activity of the radioactive device is calculated according to the radioactive characteristic peak area;

[0060] Determining the decay type and half-life of the radionuclide according to the nuclide activity, constructing a radioactive decay curve of the radionuclide according to the decay type and the half-life, and calculating the exposure dose of the radioactive device according to the radioactive decay curve;

[0061] An early warning mechanism for the radioactive equipment is constructed based on the radionuclide activity and the exposure dose, and a radioactive monitoring and management system for the radioactive equipment is constructed based on the early warning mechanism.

[0062] According to the embodiment of the present invention, by constructing the remote monitoring module of the radioactive equipment according to the material type and the material quantity, the operating status and radioactivity level of the radioactive equipment can be obtained in real time, and abnormal conditions can be discovered in time; optionally, by constructing the detector response matrix of the remote monitoring module, the embodiment of the present invention can correct the energy response of the detector through an accurate response matrix, thereby improving the resolution of gamma rays of different energies; according to the embodiment of the present invention, by constructing the nuclide identification algorithm of the radioactive equipment according to the detector response matrix, different radioactive nuclides can be more accurately identified and distinguished, thereby reducing misjudgments and missed detections; according to the embodiment of the present invention, by analyzing the radioactive characteristic peak energy and radioactive characteristic peak area of ​​the radioactive equipment according to the detector response matrix and the gamma energy spectrum of the radiation source, the accuracy and reliability of radioactive nuclide identification and activity calculation can be improved; according to the embodiment of the present invention, by calculating the exposure dose of the radioactive equipment according to the radioactive decay curve, the exposure dose can be accurately calculated, so as to monitor and control the radiation exposure of the staff and ensure that the legal dose limit is not exceeded; finally, according to the embodiment of the present invention, by constructing the radioactive monitoring and management system of the radioactive equipment according to the early warning mechanism, radiation risks caused by leakage of radioactive materials or equipment failure can be prevented through continuous monitoring and early warning, and potential accidents can be controlled. Therefore, the present invention can improve the effect of accurate monitoring of equipment radioactivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 A functional module diagram of a radioactivity monitoring and management system for inspection equipment provided by one embodiment of the present invention;

[0064] Figure 2 A schematic diagram of a flow chart of a method for monitoring and managing radioactivity of inspection equipment provided by one embodiment of the present invention;

[0065] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0067] In addition, the step sequence in the following method embodiments is only an example and not a strict limitation.

[0068] In fact, the server-side device deployed by the inspection equipment radioactivity monitoring and management system may be composed of one or more devices. The above-mentioned inspection equipment radioactivity monitoring and management system can be implemented as: business instance, virtual machine, hardware device. For example, the inspection equipment radioactivity monitoring and management system can be implemented as a business instance deployed on one or more devices in the cloud node. In simple terms, the live broadcast service system can be understood as a software deployed on the cloud node, which is used to provide inspection equipment radioactivity monitoring and management services to each user terminal. Alternatively, the inspection equipment radioactivity monitoring and management system can also be implemented as a virtual machine deployed on one or more devices in the cloud node. The virtual machine is installed with application software for managing each user terminal. Alternatively, the inspection equipment radioactivity monitoring and management system can also be implemented as a server composed of many hardware devices of the same or different types, and one or more hardware devices are set to provide inspection equipment radioactivity monitoring and management services to each user terminal.

[0069] In terms of implementation, the inspection equipment radioactivity monitoring and management system and the user end are adapted to each other. That is, the inspection equipment radioactivity monitoring and management system is an application installed on the cloud service platform, and the user end is a client that establishes a communication connection with the application; or the inspection equipment radioactivity monitoring and management system is implemented as a website, and the user end is implemented as a web page; or the inspection equipment radioactivity monitoring and management system is implemented as a cloud service platform, and the user end is implemented as a small program in an instant messaging application.

[0070] Reference Figure 1 , which is a functional module diagram of a radioactive monitoring and management system for inspection equipment provided by an embodiment of the present invention.

[0071] The inspection equipment radioactivity monitoring and management system 100 of the present invention can be set in a cloud server. In terms of implementation, it can be used as one or more service devices, or it can be installed as an application on the cloud (such as a server, server cluster, etc. for inspection equipment radioactivity monitoring and management), or it can be developed as a website. According to the functions implemented, the inspection equipment radioactivity monitoring and management system 100 includes a remote monitoring module 101, an energy spectrum analysis module 102, a nuclide identification module 103, an exposure dose analysis module 104, and a monitoring management module 105.

[0072] In the embodiment of the present invention, in the tracking based on the radioactivity monitoring management of the inspection equipment, each of the above modules can be implemented independently and called with other modules. The call here can be understood as that a certain module can connect to multiple modules of another type and provide corresponding services to the multiple modules connected to it. In the inspection equipment radioactivity monitoring and management system provided by the embodiment of the present invention, there is no need to modify the program code. The scope of application of the inspection equipment radioactivity monitoring management architecture can be adjusted by adding modules and directly calling them to achieve cluster-based horizontal expansion, so as to achieve the purpose of quickly and flexibly expanding the inspection equipment radioactivity monitoring and management system. In actual applications, the above modules can be set in the same device or different devices, or they can be set in virtual devices, such as service instances in cloud servers.

[0073] In the following, in conjunction with specific embodiments, each component and specific workflow of the inspection equipment radioactivity monitoring and management system are described respectively.

[0074] The remote monitoring module 101 is used to obtain equipment data of the radioactive equipment, identify the radioactive material of the radioactive equipment based on the equipment data, determine the material type and material quantity of the radioactive material, construct a remote monitoring module for the radioactive equipment based on the material type and the material quantity, and use the remote monitoring module to monitor the radioactive equipment to obtain equipment monitoring data.

[0075] The embodiment of the present invention can obtain the equipment data of the radioactive equipment and understand the radiation dose rate in real time through data analysis, which is of great significance for the radiation protection of the surrounding environment and workers. The equipment data refers to various information related to the radioactive equipment, such as the type of equipment and the use environment.

[0076] The embodiment of the present invention can identify the radioactive materials of the radioactive equipment based on the equipment data, and can ensure the quality control of the equipment during production and operation and prevent improper use or handling of radioactive materials through accurate identification and analysis of the radioactive materials.

[0077] Optionally, as an embodiment of the present invention, the identification of the radioactive material of the radioactive device based on the device data may be performed by radioactive tracking technology.

[0078] The embodiment of the present invention can monitor and control the potential impact of radioactive materials on the environment by determining the material type and material quantity of the radioactive material. The material type refers to the type of radioactive isotope or radioactive material. The material quantity refers to the amount of radioactive material.

[0079] The embodiment of the present invention can obtain the operating status and radioactivity level of the radioactive equipment in real time and detect abnormal conditions in time by constructing a remote monitoring module of the radioactive equipment according to the material type and the material quantity. The remote monitoring module refers to a system that uses networks, wireless communications, sensors and other related technologies to achieve remote monitoring, data collection, transmission and analysis of radiation levels and other key parameters of radioactive equipment.

[0080] As an embodiment of the present invention, the remote monitoring module of the radioactive equipment is constructed according to the material type and the material quantity, including:

[0081] Determine the monitoring requirements of the radioactive equipment according to the type of the material and the quantity of the material, and analyze the radioactive risk of the radioactive equipment;

[0082] Determining the detector of the radioactive equipment according to the monitoring requirements and the radioactive risks;

[0083] Constructing a data acquisition unit, a communication unit and a power management unit of the detector;

[0084] Constructing a monitoring network for the radioactive equipment, wherein the monitoring network includes: equipment layout, data flow and communication protocol;

[0085] Based on the monitoring network, the data acquisition unit, the communication unit, the power management unit and the detector are integrated into a remote monitoring module.

[0086] Among them, the monitoring requirements refer to the specific goals and requirements for monitoring radioactive equipment in order to ensure the safe operation and radiation protection of radioactive equipment and comply with relevant regulations and standards. The radioactive risk refers to the possibility of potential hazards and adverse effects caused by the radioactive properties of radioactive materials. The detector refers to a device that can detect and respond to a certain form of energy or physical phenomenon. The data acquisition unit refers to an electronic device or system whose function is to collect, record, process and transmit information from various sensors, instruments or other data sources. The communication unit refers to a component or module in a system or device that is responsible for sending, receiving and / or processing communication signals. The power management unit refers to a component or module in an electronic system, which is designed to effectively control, convert, distribute and monitor power. The monitoring network refers to a system composed of multiple monitoring nodes, which are interconnected by communication links and are used to collect, transmit and process data of various environmental, physical or technical parameters. The equipment layout refers to the way to reasonably arrange and arrange various equipment in a specific space or area. The data flow refers to the transmission path and direction of data in a system, network or application. The communication protocol refers to a set of rules and standards that define the format, sequence, error detection and correction methods of data transmission between communication entities, and the process of controlling information exchange.

[0087] Optionally, the analyzing the radioactive risk of the radioactive equipment may be performed by probabilistic risk analysis.

[0088] Optionally, the monitoring network for constructing the radioactive equipment may be constructed by a system integration and control method.

[0089] The embodiment of the present invention uses the remote monitoring module to monitor the radioactive equipment to obtain equipment monitoring data, which can continuously record radiation data, facilitate long-term storage and analysis, and be used for trend prediction, risk assessment and compliance reporting. The equipment monitoring data refers to various information and parameters collected from the radioactive monitoring equipment, which reflect the operating status, radiation level and possible environmental impact of the radioactive equipment.

[0090] The energy spectrum analysis module 102 is used to construct the detector response matrix of the remote monitoring module, construct the nuclide identification algorithm of the radioactive equipment according to the detector response matrix, and determine the gamma energy spectrum of the radiation source of the radioactive equipment according to the material type, the material quantity and the equipment monitoring data.

[0091] The embodiment of the present invention can correct the energy response of the detector and improve the resolution of gamma rays of different energies by constructing the detector response matrix of the remote monitoring module through an accurate response matrix. The detector response matrix refers to a mathematical tool for describing the response characteristics of the detector to gamma rays of different energies.

[0092] As an embodiment of the present invention, the detector response matrix of the remote monitoring module is constructed, including:

[0093] Determine the monitoring energy range of the detector corresponding to the remote monitoring module, and obtain a known standard source within the monitoring energy range;

[0094] Using the detector to monitor the known standard source to obtain known standard source data;

[0095] Performing energy spectrum analysis on the known standard source data to obtain an energy spectrum analysis result, and identifying the energy full energy peak of the known standard source according to the energy spectrum analysis result;

[0096] Determining the total energy peak parameters of the energy total energy peak, and fitting the energy calibration results of the total energy peak parameters;

[0097] According to the energy calibration results, respectively constructing the energy response matrix, the nuclide response matrix and the mixed response matrix of the remote monitoring module;

[0098] Based on the energy response matrix, the nuclide response matrix and the mixed response matrix, a detector response matrix of the remote monitoring module is determined.

[0099] Among them, the monitoring energy range refers to the interval in which the detector can effectively detect and identify the gamma ray energy. The known standard source refers to a radioactive source with known radioactive nuclide composition, activity (or dose rate) and gamma ray energy, which is used to calibrate, test and verify the performance of the radioactive detection system. The known standard source data refers to various parameters and information related to the known standard source. The energy spectrum analysis results refer to the data and conclusions obtained after processing and analyzing the radioactive signals collected by the detector. The energy full energy peak refers to the peak value of a specific energy formed on the energy spectrum when the full energy of gamma rays or X-rays is absorbed by the detector in the radioactive spectrum analysis. The full energy peak parameter refers to a quantitative parameter describing the characteristics of the energy full energy peak, such as peak position, peak height, peak area, etc. The energy calibration result refers to a series of data obtained by energy calibration of the detector, which establishes the corresponding relationship between the detector output signal (such as pulse height) and the incident gamma ray energy. The energy response matrix refers to a matrix that describes the response characteristics of the detector to gamma rays of different energies. The nuclide response matrix refers to a matrix used to describe the response characteristics of the detector to different radioactive nuclides. The mixed response matrix refers to a matrix formed by the response characteristics of the detector to a mixture of different radioactive nuclides in an environment where multiple nuclides exist.

[0100] Optionally, the total energy peak parameters for determining the energy total energy peak may be determined by fitting the energy total energy peak using a Gaussian function.

[0101] Optionally, the energy response matrix, the nuclide response matrix and the mixed response matrix of the remote monitoring module respectively constructed according to the energy calibration result can be constructed by a Monte Carlo simulation method.

[0102] The embodiment of the present invention can more accurately identify and distinguish different radionuclides by constructing a radioactive device nuclide identification algorithm based on the detector response matrix, thereby reducing misjudgment and missed detection. The nuclide identification algorithm refers to a computer program or method based on data analysis, which can identify and distinguish different radionuclides from signals collected by radioactive equipment.

[0103] As an embodiment of the present invention, constructing a nuclide identification algorithm for the radioactive device according to the detector response matrix includes:

[0104] monitoring the measured gamma spectrum of the radioactive equipment;

[0105] Constructing an initial algorithm for the radioactive device, and calculating the original ray spectrum of the radioactive device using the initial algorithm according to the measured gamma energy spectrum and the detector response matrix, wherein the initial algorithm includes:

[0106] r=(A T A) -1 ·A T ·s

[0107] Among them, r represents the original ray spectrum, A T represents the transposed matrix of the detector response matrix, A represents the detector response matrix, (A T A) -1 represents the detector response matrix corresponding to the transposed matrix multiplied by the inverse matrix of the detector response matrix, and s represents the measured gamma energy spectrum;

[0108] Based on the original ray spectrum, an iterative algorithm of the initial algorithm is constructed, wherein the iterative algorithm includes:

[0109] r q+1 =r q +α(A T S T Ar)

[0110] Among them, r q+1 represents the final original ray spectrum after the q+1th iteration, r q represents the iterative original ray spectrum after the qth iteration, q represents the number of iterations, α represents the local relaxation coefficient, r represents the original ray spectrum, A T represents the transposed matrix of the detector response matrix, A represents the detector response matrix, and s represents the measured gamma energy spectrum;

[0111] According to the preset iterative residual accuracy, the termination judgment condition of the iterative algorithm is determined, wherein the termination judgment condition includes:

[0112]

[0113] Among them, θ represents the preset iterative residual accuracy, r q+1 represents the final original ray spectrum after the q+1th iteration, r q represents the iterative original ray spectrum after the qth iteration, where q represents the number of iterations;

[0114] According to the initial algorithm, the iterative algorithm and the termination judgment condition, the nuclide identification algorithm of the radioactive equipment is integrated.

[0115] Among them, the measured gamma energy spectrum refers to the gamma ray energy distribution spectrum obtained by measuring the detector. The initial algorithm refers to the preliminary calculation method used to process the measured gamma energy spectrum in the process of nuclide identification and quantitative analysis. The original ray spectrum refers to the ray energy spectrum directly measured by the ray detection equipment. The transposed matrix refers to the new matrix obtained by exchanging the rows and columns of the detector response matrix. The inverse matrix refers to a special matrix of a square matrix (i.e., a matrix with equal number of rows and columns). When it is multiplied by the original matrix, the result is a unit matrix. The iterative algorithm refers to a calculation method that gradually approaches the solution of the problem by repeatedly executing a series of calculation steps. The number of iterations refers to the number of times the entire iterative process is completed when executing the iterative algorithm. The local relaxation coefficient refers to a coefficient used to adjust the update step size of the solution in the iterative algorithm. The termination judgment condition refers to a series of conditions used to determine when to stop iteration or calculation during the execution of the algorithm.

[0116] The embodiment of the present invention determines the gamma energy spectrum of the radioactive source of the radioactive device according to the material type, the material quantity and the device monitoring data, and can accurately identify different nuclides in the radioactive material by analyzing the gamma energy spectrum. The gamma energy spectrum of the radioactive source refers to the energy spectrum formed by the gamma ray emission of the radioactive material.

[0117] Optionally, as an embodiment of the present invention, determining the gamma energy spectrum of the radiation source of the radioactive equipment based on the material type, the material quantity and the equipment monitoring data can be determined by a gamma energy spectrum measurement technology.

[0118] The nuclide identification module 103 is used to analyze the radioactive characteristic peak energy and the radioactive characteristic peak area of ​​the radioactive device according to the detector response matrix and the gamma energy spectrum of the radiation source using the nuclide identification algorithm, identify the radioactive nuclide of the radioactive device according to the radioactive characteristic peak energy, and calculate the nuclide activity of the radioactive device according to the radioactive characteristic peak area.

[0119] The embodiment of the present invention can improve the accuracy and reliability of radionuclide identification and activity calculation by analyzing the radioactive characteristic peak energy and radioactive characteristic peak area of ​​the radioactive device according to the detector response matrix and the gamma energy spectrum of the radioactive source using the nuclide identification algorithm. The radioactive characteristic peak energy refers to the specific energy value of the gamma ray (γ ray) emitted by the radionuclide during the decay process. The radioactive characteristic peak area refers to the integrated count or area under the characteristic peak corresponding to a specific radionuclide in the gamma ray energy spectrum.

[0120] As an embodiment of the present invention, the method of analyzing the radioactive characteristic peak energy and the radioactive characteristic peak area of ​​the radioactive device by using the nuclide identification algorithm according to the detector response matrix and the gamma spectrum of the radiation source includes:

[0121] Constructing a response matrix-gamma spectrum of the radioactive device according to the detector response matrix and the radiation source gamma spectrum;

[0122] Determining peak position energy data and peak area of ​​the response matrix-gamma spectrum;

[0123] Based on the peak energy data and the peak area, the response matrix-gamma spectrum is reconstructed using the nuclide identification algorithm to obtain an identification algorithm-gamma spectrum;

[0124] Detecting background radiation of the recognition algorithm-gamma energy spectrum, and performing background subtraction on the recognition algorithm-gamma energy spectrum according to the background radiation to obtain a subtracted gamma energy spectrum;

[0125] The characteristic peak of the subtracted gamma spectrum is identified, and the radioactive characteristic peak energy and the radioactive characteristic peak area of ​​the characteristic peak are determined.

[0126] Among them, the response matrix-gamma energy spectrum refers to the gamma-ray energy spectrum after correction by the detector response matrix. The peak energy data refers to the energy value corresponding to each peak of the response matrix-gamma energy spectrum. The peak area refers to the area corresponding to each peak of the response matrix-gamma energy spectrum. The identification algorithm-gamma energy spectrum refers to the gamma-ray energy spectrum after iterative update of the nuclide identification algorithm. The background radiation refers to the radiation naturally existing in the environment. The post-subtraction gamma energy spectrum refers to the gamma energy spectrum obtained after removing or subtracting certain unnecessary or interfering components through a certain data processing method. The characteristic peak refers to the peak corresponding to the gamma-ray energy related to a specific radioactive nuclide in the energy spectrum in the post-subtraction gamma energy spectrum analysis.

[0127] Optionally, the peak position energy data and peak area of ​​the response matrix-gamma spectrum can be determined by spectrum processing software.

[0128] The embodiment of the present invention can identify the radioactive nuclides of the radioactive equipment according to the radioactive characteristic peak energy, which can help understand the environmental pollution status and analyze the impact on the public and the environment. The radioactive nuclides refer to those atomic species with unstable nuclei that can spontaneously emit radiation (such as alpha particles, beta particles, gamma rays or neutrons) and transform into other nuclides.

[0129] Optionally, as an embodiment of the present invention, the identification of the radioactive nuclide of the radioactive device based on the radioactive characteristic peak energy can be performed by gamma-ray spectroscopy analysis.

[0130] In the embodiment of the present invention, by calculating the radionuclide activity of the radioactive equipment according to the radioactive characteristic peak area, the radioactive contamination level in the monitoring environment can be determined and its impact on the ecosystem and public health can be analyzed. The radionuclide activity refers to the number of atoms of the radionuclide that spontaneously decays per unit time.

[0131] As an embodiment of the present invention, the step of calculating the radionuclide activity of the radioactive device according to the radioactive characteristic peak area includes:

[0132] Calculate the characteristic peak net area of ​​the radioactive characteristic peak area;

[0133] Determining the detection efficiency and detection time of the remote monitoring module corresponding to the radioactive equipment;

[0134] Analyzing the energy gamma-ray branching ratio of the characteristic peak corresponding to the characteristic peak area of ​​the radioactive characteristic peak;

[0135] According to the characteristic peak net area, the detection efficiency, the detection time and the energy gamma-ray branching ratio, the nuclide activity of the radioactive device is calculated using the following formula:

[0136]

[0137] Where H represents the activity of the nuclide, M p represents the net area of ​​characteristic peak, β γ represents the detection efficiency, F γ represents the energy gamma-ray branching ratio, and t represents the detection time.

[0138] Among them, the characteristic peak net area refers to the actual area of ​​the characteristic peak of the extracted specific radionuclide. The detection efficiency refers to the ratio of the number of rays that the detector can detect and record from the incident gamma rays to the number of rays actually incident. The detection time refers to the total time that the detector monitors the radioactive source and records the gamma ray events. The energy gamma ray branching ratio refers to the percentage of gamma rays with a specific energy emitted from a specific radionuclide to the probability of all gamma rays emitted by the nuclide.

[0139] Optionally, the detection efficiency of the remote monitoring module corresponding to the radioactive device may be determined by a detector characteristic curve.

[0140] Optionally, the analysis of the energy gamma-ray branching ratio of the characteristic peak corresponding to the characteristic peak area of ​​the radioactive characteristic peak can be analyzed by an energy spectrum fitting method.

[0141] The exposure dose analysis module 104 is used to determine the decay type and half-life of the radionuclide according to the nuclide activity, construct a radioactive decay curve of the radionuclide according to the decay type and the half-life, and calculate the exposure dose of the radioactive equipment according to the radioactive decay curve.

[0142] The embodiment of the present invention can improve the application efficiency of nuclear technology, effectively reduce radiation risks, and ensure the safety of personnel and the environment by determining the decay type and half-life of the radionuclide according to the activity of the nuclide. The decay type refers to the type of radiation emitted by the radionuclide during the decay process. The half-life refers to the time required for the amount of the radionuclide to be reduced to half of its initial amount.

[0143] As an embodiment of the present invention, determining the decay type and half-life of the radioactive nuclide according to the nuclide activity includes:

[0144] determining the radiation energy of the radionuclide;

[0145] Inferring the decay type of the radioactive nuclide according to the radiation energy, wherein the decay type includes: alpha decay, beta decay and gamma decay;

[0146] Determining the initial activity of the radionuclide and determining the measurement time of the activity of the radionuclide;

[0147] Measuring the final activity of the radionuclide according to the measurement time;

[0148] According to the initial activity, the measurement time and the final activity, the half-life of the radionuclide is calculated using the following formula:

[0149]

[0150] Among them, B 1 / 2 represents half-life, T c represents the measurement time, log represents the logarithmic function, H 0 represents the initial activity, H T Indicates the measured time T c The final activity after .

[0151] Among them, the radiation energy refers to the energy carried by the particles or electromagnetic waves emitted during the radioactive decay process. The alpha decay refers to a radioactive decay process in which an unstable nucleus is transformed into another nucleus by emitting an alpha particle (i.e., a helium nucleus composed of two protons and two neutrons). The beta decay refers to a radioactive decay process in which an unstable nucleus is transformed into another nucleus by emitting a beta particle (a high-speed electron or positron). The gamma decay refers to a radioactive decay process in which a nucleus releases excess energy by emitting gamma rays (a type of electromagnetic radiation) when it changes from an excited state (a high-energy state) to a ground state (a low-energy state). The initial activity refers to the activity of a radioactive substance at the beginning of the measurement or measurement. The measurement time refers to the time interval from the time of the initial activity measurement of the radioactive substance to the time of the final activity measurement. The final activity refers to the remaining activity of the radioactive substance after a certain time interval.

[0152] Optionally, the determination of the radiation energy of the radioactive nuclide may be determined by energy spectrum analysis.

[0153] The embodiment of the present invention can help formulate effective radiation protection measures and ensure the safety of personnel and the environment by constructing the radioactive decay curve of the radionuclide according to the decay type and the half-life, especially when handling high-activity radioactive materials. The radioactive decay curve refers to a chart showing the decay process of the radionuclide over time.

[0154] As an embodiment of the present invention, constructing the radioactive decay curve of the radionuclide according to the decay type and the half-life includes:

[0155] Determining a curve construction requirement for the radionuclide, and determining a time range for the radionuclide according to the curve construction requirement;

[0156] According to the time range, the change in the nuclide activity of the radionuclide is calculated using the following formula:

[0157]

[0158] Among them, H(a) represents the change of nuclide activity, a represents the time a corresponding to the time range, B 1 / 2 represents half-life, H 0 represents the initial activity, e represents the exponential function with base e, and ln represents the logarithmic function with base e;

[0159] The radioactive decay curve of the radioactive nuclide is fitted according to the change in the activity of the nuclide.

[0160] The curve construction requirements refer to the specific conditions and elements that need to be met when constructing the radioactive decay curve of a radionuclide. The time range refers to the interval between the start time and the end time of the selected observation or measurement of the activity of a radionuclide when constructing the radioactive decay curve. The nuclide activity change refers to the change in the radioactivity of a radionuclide over a period of time.

[0161] The embodiment of the present invention can accurately calculate the exposure dose by calculating the exposure dose of the radioactive equipment according to the radioactive decay curve, so as to monitor and control the radiation exposure of the staff and ensure that the legal dose limit is not exceeded. The exposure dose refers to the total amount of radiation received by an individual or group due to exposure to an ionizing radiation source within a specific period of time.

[0162] As an embodiment of the present invention, the step of calculating the exposure dose of the radioactive device according to the radioactive decay curve includes:

[0163] Acquiring an exposure position, and measuring a distance between the exposure position and the radioactive device;

[0164] Determining the current nuclide activity of the radioactive device according to the radioactive decay curve;

[0165] analyzing a dose rate constant of the radioactive device;

[0166] The exposure dose of the radioactive device is calculated according to the dose rate constant, the distance and the current nuclide activity using the following formula:

[0167]

[0168] Where G represents the exposure dose, H d represents the current nuclide activity, k represents the dose rate constant, and L represents the distance.

[0169] The exposure location refers to a specific place or position where a person or equipment may be exposed to radioactive radiation. The dose rate constant refers to the dose rate generated by a radioactive source of unit activity at a reference position under specific conditions.

[0170] Optionally, the analysis of the dose rate constant of the radioactive device may be performed by a dose function method, wherein the dose function method refers to calculating the dose rate constant using a known dose function or dose rate distribution formula in combination with the characteristics and geometric position of the radioactive source.

[0171] The monitoring and management module 105 is used to construct an early warning mechanism for the radioactive equipment according to the nuclide activity and the exposure dose, and to construct a radioactive monitoring and management system for the radioactive equipment according to the early warning mechanism.

[0172] The embodiment of the present invention can help prevent radiation accidents by constructing an early warning mechanism for the radioactive equipment based on the radionuclide activity and the exposure dose, and reduce the possibility of accidents by responding to potential safety issues in a timely manner. The early warning mechanism refers to a system for monitoring and controlling potential risks of radioactive equipment.

[0173] Optionally, as an embodiment of the present invention, the early warning mechanism for the radioactive equipment based on the activity of the nuclide and the exposure dose may be constructed by an automatic alarm system.

[0174] The embodiment of the present invention constructs a radioactive monitoring and management system for the radioactive equipment according to the early warning mechanism, which can prevent radiation risks caused by leakage of radioactive materials or equipment failure and control potential accidents through continuous monitoring and early warning.

[0175] According to the embodiment of the present invention, by constructing the remote monitoring module of the radioactive equipment according to the material type and the material quantity, the operating status and radioactivity level of the radioactive equipment can be obtained in real time, and abnormal conditions can be discovered in time; optionally, by constructing the detector response matrix of the remote monitoring module, the embodiment of the present invention can correct the energy response of the detector through an accurate response matrix, thereby improving the resolution of gamma rays of different energies; according to the embodiment of the present invention, by constructing the nuclide identification algorithm of the radioactive equipment according to the detector response matrix, different radioactive nuclides can be more accurately identified and distinguished, thereby reducing misjudgments and missed detections; according to the embodiment of the present invention, by analyzing the radioactive characteristic peak energy and radioactive characteristic peak area of ​​the radioactive equipment according to the detector response matrix and the gamma energy spectrum of the radiation source, the accuracy and reliability of radioactive nuclide identification and activity calculation can be improved; according to the embodiment of the present invention, by calculating the exposure dose of the radioactive equipment according to the radioactive decay curve, the exposure dose can be accurately calculated, so as to monitor and control the radiation exposure of the staff and ensure that the legal dose limit is not exceeded; finally, according to the embodiment of the present invention, by constructing the radioactive monitoring and management system of the radioactive equipment according to the early warning mechanism, radiation risks caused by leakage of radioactive materials or equipment failure can be prevented through continuous monitoring and early warning, and potential accidents can be controlled. Therefore, the present invention can improve the effect of accurate monitoring of equipment radioactivity.

[0176] like Figure 2 FIG. 1 is a flow chart of a method for monitoring and managing radioactivity of inspection equipment provided by an embodiment of the present invention. In this embodiment, the method for monitoring and managing radioactivity of inspection equipment includes:

[0177] Acquire equipment data of a radioactive device, identify the radioactive material of the radioactive device according to the equipment data, determine the material type and material quantity of the radioactive material, construct a remote monitoring module for the radioactive device according to the material type and the material quantity, monitor the radioactive device using the remote monitoring module, and obtain equipment monitoring data;

[0178] Constructing a detector response matrix of the remote monitoring module, constructing a nuclide identification algorithm for the radioactive device based on the detector response matrix, and determining a gamma energy spectrum of the radioactive source of the radioactive device based on the material type, the material quantity and the device monitoring data;

[0179] According to the detector response matrix and the gamma energy spectrum of the radiation source, the radioactive characteristic peak energy and the radioactive characteristic peak area of ​​the radioactive device are analyzed by using the radionuclide identification algorithm, the radioactive nuclide of the radioactive device is identified according to the radioactive characteristic peak energy, and the nuclide activity of the radioactive device is calculated according to the radioactive characteristic peak area;

[0180] Determining the decay type and half-life of the radionuclide according to the nuclide activity, constructing a radioactive decay curve of the radionuclide according to the decay type and the half-life, and calculating the exposure dose of the radioactive device according to the radioactive decay curve;

[0181] An early warning mechanism for the radioactive equipment is constructed based on the radionuclide activity and the exposure dose, and a radioactive monitoring and management system for the radioactive equipment is constructed based on the early warning mechanism.

[0182] In the several embodiments provided by the present invention, it should be understood that the provided system and method can be implemented in other ways. For example, the system embodiment described above is only illustrative, for example, the division of the modules is only a logical function division, and there may be other division methods in actual implementation.

[0183] In addition, each functional module in each embodiment of the present invention may be integrated into one processing unit, each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of hardware plus software functional modules.

[0184] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A radioactivity monitoring and management system for inspection equipment, characterized in that: The system inspection equipment radioactivity monitoring management includes: a remote monitoring module, an energy spectrum analysis module, a nuclide identification module, an exposure dose analysis module and a monitoring management module; The remote monitoring module is used to obtain equipment data of the radioactive equipment, identify the radioactive material of the radioactive equipment according to the equipment data, determine the material type and material quantity of the radioactive material, build a remote monitoring module for the radioactive equipment according to the material type and the material quantity, and use the remote monitoring module to monitor the radioactive equipment to obtain equipment monitoring data; The energy spectrum analysis module is used to construct the detector response matrix of the remote monitoring module, construct the nuclide identification algorithm of the radioactive equipment according to the detector response matrix, and determine the gamma energy spectrum of the radioactive source of the radioactive equipment according to the material type, the material quantity and the equipment monitoring data; The nuclide identification module is used to analyze the radioactive characteristic peak energy and radioactive characteristic peak area of ​​the radioactive device according to the detector response matrix and the gamma energy spectrum of the radiation source using the nuclide identification algorithm, identify the radioactive nuclide of the radioactive device according to the radioactive characteristic peak energy, and calculate the nuclide activity of the radioactive device according to the radioactive characteristic peak area; The exposure dose analysis module is used to determine the decay type and half-life of the radionuclide according to the nuclide activity, construct a radioactive decay curve of the radionuclide according to the decay type and the half-life, and calculate the exposure dose of the radioactive device according to the radioactive decay curve; The monitoring and management module is used to construct an early warning mechanism for the radioactive equipment according to the nuclide activity and the exposure dose, and to construct a radioactive monitoring and management system for the radioactive equipment according to the early warning mechanism.

2. The inspection equipment radioactivity monitoring and management system according to claim 1, characterized in that: The remote monitoring module of the radioactive equipment is constructed according to the material type and the material quantity, including: Determine the monitoring requirements of the radioactive equipment according to the type of the material and the quantity of the material, and analyze the radioactive risk of the radioactive equipment; Determining the detector of the radioactive equipment according to the monitoring requirements and the radioactive risks; Constructing a data acquisition unit, a communication unit and a power management unit of the detector; Constructing a monitoring network for the radioactive equipment, wherein the monitoring network includes: equipment layout, data flow and communication protocol; Based on the monitoring network, the data acquisition unit, the communication unit, the power management unit and the detector are integrated into a remote monitoring module.

3. The inspection equipment radioactivity monitoring and management system according to claim 2, characterized in that: The detector response matrix of the remote monitoring module is constructed, including: Determine the monitoring energy range of the detector corresponding to the remote monitoring module, and obtain a known standard source within the monitoring energy range; Using the detector to monitor the known standard source to obtain known standard source data; Performing energy spectrum analysis on the known standard source data to obtain an energy spectrum analysis result, and identifying the energy full energy peak of the known standard source according to the energy spectrum analysis result; Determining the total energy peak parameters of the energy total energy peak, and fitting the energy calibration results of the total energy peak parameters; According to the energy calibration results, respectively constructing the energy response matrix, the nuclide response matrix and the mixed response matrix of the remote monitoring module; Based on the energy response matrix, the nuclide response matrix and the mixed response matrix, a detector response matrix of the remote monitoring module is determined.

4. The inspection equipment radioactivity monitoring and management system according to claim 1, characterized in that: The step of constructing a nuclide identification algorithm for the radioactive device according to the detector response matrix includes: monitoring the measured gamma spectrum of the radioactive equipment; Constructing an initial algorithm for the radioactive device, and calculating the original ray spectrum of the radioactive device using the initial algorithm according to the measured gamma energy spectrum and the detector response matrix; Based on the original ray spectrum, construct an iterative algorithm of the initial algorithm; Determining a termination judgment condition of the iterative algorithm according to the preset iterative residual accuracy; According to the initial algorithm, the iterative algorithm and the termination judgment condition, the nuclide identification algorithm of the radioactive equipment is integrated.

5. The inspection equipment radioactivity monitoring and management system according to claim 1, characterized in that: The method of analyzing the radioactive characteristic peak energy and the radioactive characteristic peak area of ​​the radioactive device by using the nuclide identification algorithm according to the detector response matrix and the radioactive source gamma spectrum includes: Constructing a response matrix-gamma spectrum of the radioactive device according to the detector response matrix and the radiation source gamma spectrum; Determining peak position energy data and peak area of ​​the response matrix-gamma spectrum; Based on the peak energy data and the peak area, the response matrix-gamma spectrum is reconstructed using the nuclide identification algorithm to obtain an identification algorithm-gamma spectrum; Detecting background radiation of the recognition algorithm-gamma energy spectrum, and performing background subtraction on the recognition algorithm-gamma energy spectrum according to the background radiation to obtain a subtracted gamma energy spectrum; The characteristic peak of the subtracted gamma spectrum is identified, and the radioactive characteristic peak energy and the radioactive characteristic peak area of ​​the characteristic peak are determined.

6. The inspection equipment radioactivity monitoring and management system according to claim 1, characterized in that The calculating the nuclide activity of the radioactive device according to the radioactive characteristic peak area comprises: Calculate the characteristic peak net area of ​​the radioactive characteristic peak area; Determining the detection efficiency and detection time of the remote monitoring module corresponding to the radioactive equipment; Analyzing the energy gamma-ray branching ratio of the characteristic peak corresponding to the characteristic peak area of ​​the radioactive characteristic peak; According to the characteristic peak net area, the detection efficiency, the detection time and the energy gamma ray branching ratio.

7. The inspection equipment radioactivity monitoring and management system according to claim 1, characterized in that: Determining the decay type and half-life of the radioactive nuclide according to the nuclide activity includes: determining the radiation energy of the radionuclide; Inferring the decay type of the radioactive nuclide according to the radiation energy, wherein the decay type includes: alpha decay, beta decay and gamma decay; Determining the initial activity of the radionuclide and determining the measurement time of the activity of the radionuclide; Measuring the final activity of the radionuclide according to the measurement time; According to the initial activity, the measurement time and the final activity.

8. The inspection equipment radioactivity monitoring and management system according to claim 1, characterized in that: The step of constructing a radioactive decay curve of the radionuclide according to the decay type and the half-life includes: Determining a curve construction requirement for the radionuclide, and determining a time range for the radionuclide according to the curve construction requirement; Based on the time frame stated.

9. The inspection equipment radioactivity monitoring and management system according to claim 1, characterized in that: Calculating the exposure dose of the radioactive device according to the radioactive decay curve includes: Acquiring an exposure position, and measuring a distance between the exposure position and the radioactive device; Determining the current nuclide activity of the radioactive device according to the radioactive decay curve; analyzing a dose rate constant of the radioactive device; According to the dose rate constant, the distance and the current nuclide activity.

10. A method for monitoring and managing radioactivity of inspection equipment, characterized in that: The method comprises: Acquire equipment data of a radioactive device, identify the radioactive material of the radioactive device according to the equipment data, determine the material type and material quantity of the radioactive material, construct a remote monitoring module for the radioactive device according to the material type and the material quantity, monitor the radioactive device using the remote monitoring module, and obtain equipment monitoring data; Constructing a detector response matrix of the remote monitoring module, constructing a nuclide identification algorithm for the radioactive device based on the detector response matrix, and determining a gamma energy spectrum of the radioactive source of the radioactive device based on the material type, the material quantity and the device monitoring data; According to the detector response matrix and the gamma energy spectrum of the radiation source, the radioactive characteristic peak energy and the radioactive characteristic peak area of ​​the radioactive device are analyzed by using the radionuclide identification algorithm, the radioactive nuclide of the radioactive device is identified according to the radioactive characteristic peak energy, and the nuclide activity of the radioactive device is calculated according to the radioactive characteristic peak area; Determining the decay type and half-life of the radionuclide according to the nuclide activity, constructing a radioactive decay curve of the radionuclide according to the decay type and the half-life, and calculating the exposure dose of the radioactive device according to the radioactive decay curve; An early warning mechanism for the radioactive equipment is constructed based on the radionuclide activity and the exposure dose, and a radioactive monitoring and management system for the radioactive equipment is constructed based on the early warning mechanism.

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