Radioactive third party responsibility risk economic quantification method, device, equipment and medium

Abstract

The invention discloses a radioactive third party responsibility risk economic quantification method, device, equipment and medium, and the method comprises the steps: recognizing and analyzing accident sequences causing radioactive release based on a secondary probability safety evaluation model of a nuclear power station, and generating the annual occurrence frequency of each accident sequence, the release activity of each radionuclide in preset release classification in the accident sequence is calculated, and a release category list and a nuclide release spectrum of each target release category are obtained; sampling a target weather sequence, calculating time integral air concentration and ground deposition concentration, and calculating personal radiation dose and collective radiation dose; calculating early-stage health effect people number and late-stage health effect people number; calculating the total economic loss caused by the radioactive release accident; fitting based on the annual occurrence frequency and the total economic loss to obtain an aggregation risk curve; and carrying out statistics on preset indexes based on the aggregation risk curve to generate a target risk statistical result. According to the invention, accurate quantitative evaluation of radioactive release consequences is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of nuclear emergency, and can be applied to the fields of medical health and financial payment, and particularly relates to a radioactive third party liability risk economic quantification method, device, equipment and medium. BACKGROUND

[0002] With the continuous development of the nuclear power industry, radioactive third party liability insurance, as an important risk transfer tool, plays an important role in reducing the risk of operating units and promoting the healthy development of the nuclear industry. Radioactive third party liability insurance has attracted more and more attention from the government and nuclear power operating units, and has become an indispensable insurance guarantee for the operation of nuclear power plants.

[0003] At present, radioactive third party liability insurance is quite mature, which ensures that there is sufficient funds for post-processing after a nuclear accident. The existing radioactive third party liability insurance mechanism has problems such as insurance vacancy and insufficient liability limit of the insurance policy. Limited by the lack of overall assessment of radioactive third party liability after a nuclear accident, it is impossible to accurately calculate the loss data of nuclear third party liability risk, which limits the further development of nuclear third party liability insurance. For the quantification of radioactive third party liability risk, the first / second level probabilistic safety assessment (PSA) has completed the quantitative calculation of the core damage frequency and the radioactive release source term, but there are the following technical defects: first, the existing technology fails to fully consider the development process of the environment after radioactive release, and cannot accurately simulate the diffusion behavior of radioactive nuclides in the atmosphere; second, the existing assessment method lacks economic assessment of radioactive consequences, and it is difficult to quantify the economic losses caused by nuclear accidents; finally, although the existing actuarial method can solve the establishment of risk curve and quantitative result output, it lacks probability and consequence data related to radioactive source term, resulting in inaccurate risk assessment results. Probabilistic safety assessment and actuarial science have commonalities in probability statistics, but the existing technology has not effectively combined the two to systematically solve the problem of nuclear third party liability risk quantification. In view of the above problems, the existing technology needs to be improved. SUMMARY

[0004] The purpose of the embodiments of the present application is to provide a radioactive third party liability risk economic quantification method, device, equipment and medium, which has the advantages of realizing accurate quantitative assessment of radioactive release consequences, fully considering the influence of environmental factors on radioactive diffusion, and effectively combining probabilistic safety assessment and actuarial method to improve the accuracy of risk assessment.

[0005] To solve the above technical problems, the embodiments of the present application provide a radioactive third party liability risk economic quantification method, which comprises:

[0006] The nuclear power plant-based secondary probabilistic safety assessment model identifies and analyzes an accident sequence causing radioactive release, generates an annual occurrence frequency of each of the accident sequences, and calculates a release activity of each radionuclide in a preset release classification in the accident sequence, to obtain a release classification list and a radionuclide release spectrum of each target release classification;

[0007] Obtain annual hourly meteorological data of a nuclear power plant site, randomly sample target weather sequences, and for each of the target release classifications and the target weather sequences, calculate a time-integrated air concentration and a ground deposition concentration of radionuclides at each spatial grid point in the downwind direction after atmospheric diffusion based on the radionuclide release spectrum;

[0008] Based on the time-integrated air concentration and the ground deposition concentration, combined with pre-stored dose conversion factors and population distribution data of the nuclear power plant site, calculate the individual radiation dose and the collective radiation dose, and according to the protection action data, dose correct the individual radiation dose and the collective radiation dose, to generate target individual radiation dose and target collective radiation dose;

[0009] Using a probabilistic model, calculate the number of expected early health effects and the number of expected late health effects based on the target individual radiation dose;

[0010] Based on the number of early health effects and the number of late health effects, calculate the economic loss of personnel caused by the radioactive release accident, based on the ground deposition concentration and the target individual radiation dose, calculate the economic loss of material caused by the radioactive release accident, and based on the economic loss of personnel and the economic loss of material, calculate the total economic loss, wherein the economic loss of personnel includes compensation for casualties and emergency response costs, and the economic loss of material includes decontamination costs, agricultural / non-agricultural short-term blockade costs, agricultural / non-agricultural confiscation costs, evacuation and relocation costs, and crop disposal costs;

[0011] Based on the annual occurrence frequency of the target release classification, the annual occurrence frequency of the target weather sequence, and the total economic loss, perform risk curve fitting to obtain an aggregated risk curve;

[0012] Sample the aggregated risk curve to generate a loss sample set, and based on the loss sample set, perform statistics on a preset index to generate a target risk statistical result.

[0013] To solve the above technical problems, an embodiment of the present application provides a radioactive third party liability risk economic quantification device, comprising:

[0014] The release activity calculation module is configured to identify and analyze an accident sequence causing radioactive release based on a secondary probabilistic safety assessment model of the nuclear power plant, generate an annual occurrence frequency of each of the accident sequences, and calculate a release activity of each radionuclide in a preset release classification in the accident sequence, to obtain a release classification list and a radionuclide release spectrum of each target release classification.

[0015] The concentration calculation module is configured to obtain annual hourly meteorological data of a site of the nuclear power plant, randomly sample a target weather sequence, and calculate, for each of the target release classifications and the target weather sequence, a time-integrated air concentration and a ground deposition concentration of radionuclides at each spatial grid point in a downwind direction after atmospheric diffusion based on the radionuclide release spectrum.

[0016] The radiation dose calculation module is configured to calculate, based on the time-integrated air concentration and the ground deposition concentration, a personal radiation dose and a collective radiation dose in combination with a pre-stored dose conversion factor and population distribution data of the site of the nuclear power plant, and perform dose correction on the personal radiation dose and the collective radiation dose according to protection action data, to generate a target personal radiation dose and a target collective radiation dose.

[0017] The effect population calculation module is configured to calculate, based on the target personal radiation dose, an early health effect population and a late health effect population expected to occur by using a probabilistic model.

[0018] The economic loss calculation module is configured to calculate, based on the early health effect population and the late health effect population, a personnel economic loss caused by the radioactive release accident, calculate, based on the ground deposition concentration and the target personal radiation dose, a material economic loss caused by the radioactive release accident, and calculate a total economic loss based on the personnel economic loss and the material loss, wherein the personnel economic loss includes a personnel casualty compensation and an emergency response cost, and the material economic loss includes a decontamination cost, an agricultural / non-agricultural short-term blockade cost, an agricultural / non-agricultural confiscation cost, an evacuation relocation cost, and a crop disposal cost.

[0019] The curve fitting module is configured to perform risk curve fitting based on the annual occurrence frequency of the target release classification, the annual occurrence frequency of the target weather sequence, and the total economic loss, to obtain an aggregated risk curve.

[0020] The statistical result generation module is configured to sample the aggregated risk curve to generate a loss sample set, and perform statistics on a preset index based on the loss sample set to generate a target risk statistical result.

[0021] To solve the above technical problems, one technical solution adopted by the present application is to provide a computer device, comprising one or more processors; a memory for storing one or more programs, so that the one or more processors implement the radioactive third party liability risk economic quantification method described in any one of the above.

[0022] To solve the above technical problems, one technical solution adopted by the present application is a computer readable storage medium, the computer readable storage medium has a computer program stored thereon, and the computer program is executed by a processor to implement the radioactive third party liability risk economic quantification method described in any one of the above.

[0023] The embodiment of the present application provides a radioactive third party liability risk economic quantification method, device, equipment and medium. The method comprises the following steps: identifying and analyzing an accident sequence causing radioactive release based on a secondary probabilistic safety assessment model of a nuclear power plant, generating an annual occurrence frequency of each accident sequence, and calculating a release activity of each radionuclide in a preset release classification in the accident sequence to obtain a release classification list and a nuclide release spectrum of each target release classification; obtaining annual hourly meteorological data of the nuclear power plant site, randomly sampling a target weather sequence, and for each target release classification and the target weather sequence, calculating the time-integrated air concentration and the ground deposition concentration of the radionuclide at each spatial grid point in the downwind direction after atmospheric diffusion based on the nuclide release spectrum; calculating the individual radiation dose and the collective radiation dose based on the time-integrated air concentration and the ground deposition concentration, combining the pre-stored dose conversion factor and the population distribution data of the nuclear power plant site, and performing dose correction on the individual radiation dose and the collective radiation dose according to the protection action data to generate a target individual radiation dose and a target collective radiation dose; calculating the number of expected early health effects and the number of expected late health effects based on the target individual radiation dose by using a probability model; calculating the personnel economic loss caused by the radioactive release accident based on the number of early health effects and the number of late health effects, calculating the material economic loss caused by the radioactive release accident based on the ground deposition concentration and the target individual radiation dose, and calculating the total economic loss based on the personnel economic loss and the material loss, wherein the personnel economic loss comprises personnel casualty compensation and emergency response cost, and the material economic loss comprises decontamination cost, agricultural / non-agricultural short-term blockade cost, agricultural / non-agricultural confiscation cost, evacuation and relocation cost, and crop disposal cost; fitting a risk curve based on the annual occurrence frequency of the target release classification, the annual occurrence frequency of the target weather sequence and the total economic loss to obtain an aggregated risk curve; sampling the aggregated risk curve to generate a loss sample set, and performing statistics on a preset index based on the loss sample set to generate a target risk statistical result. The present application integrates the secondary probabilistic safety assessment model, the meteorological data simulation, the dose calculation model and the economic loss evaluation, establishes a full-chain quantification model from the radioactive release source term to the economic loss, combines the risk curve fitting technology, realizes the accurate economic quantification of the radioactive third party liability risk, and has the advantages of accurate evaluation result, comprehensive coverage of environmental factors and support for insurance actuarial decision. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the scheme in the present application, the drawings needed in the embodiment description of the present application will be briefly introduced as follows. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating laborious work.

[0025] Figure 1 is an implementation flowchart of the radioactive third party liability risk economic quantification method provided by the embodiment of the present application;

[0026] Figure 2 is an implementation flowchart of the first sub-process of the radioactive third party liability risk economic quantification method provided by the embodiment of the present application;

[0027] Figure 3 is an implementation flowchart of the second sub-process of the radioactive third party liability risk economic quantification method provided by the embodiment of the present application;

[0028] Figure 4 is an atmospheric diffusion calculation flowchart provided by the embodiment of the present application;

[0029] Figure 5 is an implementation flowchart of the third sub-process of the radioactive third party liability risk economic quantification method provided by the embodiment of the present application;

[0030] Figure 6 is an implementation flowchart of the fourth sub-process of the radioactive third party liability risk economic quantification method provided by the embodiment of the present application;

[0031] Figure 7 is an implementation flowchart of the fifth sub-process of the radioactive third party liability risk economic quantification method provided by the embodiment of the present application;

[0032] Figure 8 is an implementation flowchart of the sixth sub-process of the radioactive third party liability risk economic quantification method provided by the embodiment of the present application;

[0033] Figure 9 is an implementation flowchart of the seventh sub-process of the radioactive third party liability risk economic quantification method provided by the embodiment of the present application;

[0034] Figure 10 is an implementation flowchart of the eighth sub-process of the radioactive third party liability risk economic quantification method provided by the embodiment of the present application;

[0035] Figure 11 is a radioactive third party liability risk economic quantification device schematic diagram provided by the embodiment of the present application;

[0036] Figure 12 is a computer device schematic diagram provided by the embodiment of the present application. DETAILED DESCRIPTION

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application; the use herein of terms such as "comprise" and "comprising", "have" and "having", "include" and "including" and "contain" and "containing" are to be construed in an open, non-exclusive way, as comprising the stated features, integers, steps and / or elements but not precluding the addition of one or more other features, integers, steps, processes, agents, compounds, compositions, steps and / or elements thereof; the use herein of terms such as "first", "second" and "other" are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order.

[0038] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase "in an embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another.

[0039] In order to better understand the technical solutions of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings.

[0040] In the prior art, the nuclear energy field has long relied on probabilistic safety assessment methods for radioactive release source term calculation, but lacks dynamic simulation of atmospheric diffusion process and economic consequence assessment. Although the traditional actuarial method can establish a risk model, it is difficult to obtain radioactive release probability and dose distribution data. The international mature insurance mechanism relies on historical data support, while in China, due to the lack of accident consequence quantification model, there is a significant gap in risk assessment, which restricts the design of insurance products and the determination of liability limits.

[0041] In order to solve the above problems, the inventors found that the prior art cannot effectively integrate physical accident models and economic loss assessment, resulting in insufficient accuracy of nuclear third party liability risk quantification. Through analysis, it is found that economic assessment of radioactive consequences needs to consider multiple factors such as release probability, dynamic influence of meteorological conditions, dose conversion relationship and population distribution. Based on this, a two-stage probabilistic safety assessment and actuarial method are combined to construct a full-chain calculation model from accident sequence to economic loss, the Monte Carlo method is used to simulate the influence of weather changes on the diffusion process, a mapping relationship between dose-health effect-economic loss is established, and finally the loss distribution of different scenarios is aggregated through the risk curve.

[0042] Therefore, the application proposes a secondary probabilistic safety assessment model based on a nuclear power plant to identify and analyze the accident sequence leading to radioactive release, generate the annual occurrence frequency of each accident sequence, and calculate the release activity of each radionuclide in the preset release classification in the accident sequence to obtain a release classification list and a radionuclide release spectrum of each target release classification; obtain the annual hourly meteorological data of the nuclear power plant site, randomly sample a target weather sequence, and for each target release classification and target weather sequence, calculate the time-integrated air concentration and ground deposition concentration of radionuclides at each spatial grid point in the downwind direction after atmospheric diffusion based on the radionuclide release spectrum; based on the time-integrated air concentration and the ground deposition concentration, combined with the pre-stored dose conversion factor and the population distribution data of the nuclear power plant site, calculate the individual radiation dose and the collective radiation dose, and dose correct the individual radiation dose and the collective radiation dose according to the protection action data to generate a target individual radiation dose and a target collective radiation dose; using a probability model, the number of expected early health effects and the number of expected late health effects are calculated based on the individual radiation dose; the total economic loss caused by the radioactive release accident is calculated based on the number of early health effects and the number of late health effects; based on the annual occurrence frequency of the target release classification, the annual occurrence frequency of the target weather sequence, and the total economic loss, a risk curve is fitted to obtain an aggregated risk curve; the aggregated risk curve is sampled to generate a loss sample set, and a target risk statistical result is generated based on the loss sample set for a preset index.

[0043] The secondary probabilistic safety assessment model refers to a calculation tool for analyzing the accident development path of a nuclear power plant, which can be specifically implemented by combining event trees and fault trees, and provides basic data for subsequent risk assessment by quantifying the accident sequence occurrence probability. The radionuclide release spectrum refers to the activity distribution data of different radionuclides in the accident release process, which can be specifically generated by simulating the containment failure process using the MAAP program, and is used to represent the composition characteristics of each release classification of radioactive substances. The time-integrated air concentration refers to the concentration value of radionuclides accumulated in the air over time, which can be specifically obtained by piecewise calculation and accumulation using an atmospheric diffusion model, and reflects the key parameters for exposure dose calculation. The ground deposition concentration refers to the concentration of radioactive substances deposited on the ground, which can be specifically calculated by multiplying the dry and wet deposition velocity and the air concentration, and is used to evaluate the degree of ground contamination. The dose conversion factor refers to the radiation dose coefficient generated by a unit of radioactive concentration on the human body, which can be specifically implemented by using the values published by the International Commission on Radiological Protection to convert physical concentration to biological effects. The aggregated risk curve refers to the relationship curve between the probability of occurrence of different accident scenarios and the corresponding economic loss, which can be specifically generated by fitting discrete data points using the kernel density estimation method, and is used to represent the overall risk distribution characteristics.

[0044] Specifically, firstly, a two-level probabilistic safety assessment model is used to identify accident sequences that may trigger radioactive releases, calculate the annual frequency of each sequence, and classify them into standardized release categories based on release characteristics. For each release category, a release spectrum including nuclide species and activities is generated using thermal-hydraulic analysis software. Subsequently, hourly meteorological data for the nuclear power plant site throughout the year is acquired, and representative weather sequences are generated using the Monte Carlo method. A Gaussian plume model is then used to calculate the air and surface concentration distribution at each grid point. Based on a dose conversion factor, the concentration data is converted into individual and collective doses, and a probabilistic health effect model is applied to predict the number of cases in different population groups. By integrating economic parameters such as medical costs and property damage, the number of people affected by health effects is converted into economic loss values. Finally, risk data from all release categories and weather sequences are aggregated, a curve describing the probability distribution of losses is fitted, and a risk quantification index is output through statistical sampling. This application organically combines the release frequency data from probabilistic safety assessments with actuarial loss distribution calculations, achieving a linked analysis of the physical processes and economic consequences of accidents. Compared to static meteorological assumptions, dynamic weather sampling technology more realistically reflects the variability of actual diffusion scenarios. By establishing a multi-path dose calculation model, the accuracy of health effect predictions has been improved. The risk curve aggregation method effectively solves the integration challenge of multi-source and multi-scenario data. This application achieves dynamic quantitative assessment of the radioactive consequences of nuclear accidents, resolving the assessment bias caused by neglecting environmental factors in traditional methods. By integrating probabilistic safety assessment data and actuarial models, a complete risk assessment chain is constructed, providing reliable data support for determining insurance liability limits. The use of Monte Carlo weather sampling and segmented diffusion calculations significantly improves the spatiotemporal resolution of atmospheric diffusion simulation. By establishing a multi-dimensional economic loss calculation model, full-element coverage from physical release to economic compensation is achieved, filling the gap in domestic nuclear third-party liability risk quantification technology.

[0045] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0046] Please see Figure 1 , Figure 1 This paper illustrates a specific implementation method for the economic quantification of radioactive third-party liability risk.

[0047] It should be noted that if substantially the same result is obtained, the method of this invention is not based on... Figure 2 Limited to the order of the processes shown, this method includes the following steps:

[0048] S1: Based on the secondary probabilistic safety assessment model of nuclear power plants, identify and analyze accident sequences that lead to radioactive release, generate the annual occurrence frequency of each accident sequence, and calculate the release activity of each radionuclide in the accident sequence that is pre-classified for release, so as to obtain a list of release categories and the release spectrum of radionuclides for each target release category.

[0049] Specifically, to evaluate the release risk of fission products when the containment fails, a secondary probabilistic safety assessment model is used to analyze the radioactive source term to obtain the annual frequency of each accident sequence. In the embodiment of the present application, according to the principle of the highest release frequency and the most serious consequences, a plurality of representative release categories are selected as target release categories, the MAAP program is used to calculate the release activity of each radionuclide in the target release categories, and a release category list and a nuclide release spectrum of each target release category are obtained. The release category list includes the qualitative description of each target release category and its annual frequency. The nuclide release spectrum of each release category includes the release amount of each nuclide in each target release category.

[0050] Please refer to Figure 2 , Figure 2 An embodiment of step S1 is shown as follows:

[0051] S11: Obtain the PSA model data and power plant design parameters of the nuclear power plant, and perform identification analysis based on the power plant design parameters through the secondary probabilistic safety assessment model to calculate the annual frequency of each accident sequence. S12: Classify the accident sequences according to the characteristics of radioactive release to obtain release categories, wherein the annual frequency of each release category is the sum of the frequencies of all accident sequences contained in the release category. S13: Screen the release categories according to a preset screening rule to obtain a release category list, wherein the release category list includes a plurality of target release categories and the annual frequency of each target release category. S14: For each target release category, the total activity of each radionuclide released from the containment to the environment is obtained by using the MAAP program to obtain the nuclide release spectrum of each target release category.

[0052] The PSA model data refers to the event tree, fault tree and basic event failure probability data contained in the probabilistic safety assessment model, which can be obtained by matching the nuclear power plant operation history data and the equipment reliability database, and is used to construct the logical model of the accident sequence. The power plant design parameters refer to the reactor containment structure characteristics, ventilation system layout and radioactive material retention coefficient, which can be extracted by three-dimensional modeling and thermal-hydraulic analysis tools, and are used to determine the radionuclide release path. The release category refers to a set of accident sequences with the same radioactive release characteristics, which can be clustered and divided by radionuclide release amount, release duration and release height, and is used to simplify the subsequent diffusion calculation. The preset screening rule refers to an algorithm for screening categories based on release frequency threshold and radioactive hazard weight, for example, the release frequency threshold can be set to 1E-6 times per year, and the hazard weight is calculated by the half-life of the radionuclide and the dose conversion factor, which is used to exclude the release categories with low risk contribution. The MAAP program refers to a severe accident analysis tool, which can calculate the total release activity of each radionuclide from the containment to the environment by inputting the containment failure mode and the fission product release model, and is used to generate quantitative data of the radionuclide release spectrum.

[0053] Specifically, by integrating the PSA model data and the power plant design parameters, the secondary probabilistic safety assessment model can identify a complete set of accident sequences that cause radioactive release. The annual occurrence frequency of each accident sequence is obtained by multiplying the top event probability of the event tree and the minimal cut set probability of the fault tree. After the accident sequences are classified according to the release characteristics, the annual frequency of each release category is obtained by accumulating the frequencies of all accident sequences it contains. The preset screening rule optimizes the screening of the release categories, for example, only the categories with annual frequency higher than 1E-7 times and containing key radionuclides such as iodine-131 or cesium-137 are retained. The target release categories after screening are calculated for radionuclide release amount by the MAAP program, the input parameters include containment failure time, fission product release share and decay correction coefficient, and finally the release activity matrix of different radionuclides in each target release category is output.

[0054] S2: Obtain the annual hourly meteorological data of the nuclear power plant site, randomly sample the target weather sequence, and for each of the target release categories and the target weather sequence, calculate the time-integrated air concentration and ground deposition concentration of the radionuclide at each spatial grid point in the downwind direction after atmospheric diffusion based on the radionuclide release spectrum.

[0055] Specifically, hourly meteorological data for the target nuclear power plant is collected for the entire year. The hourly meteorological data includes hourly wind direction, wind speed, and hourly cumulative rainfall observed from the site's meteorological tower. Atmospheric stability at each moment is calculated using a temperature gradient and wind speed classification method. Since the accident could occur at any time within the 8760 hours of the year, the hourly meteorological data is sampled to select representative weather sequences. In this embodiment, the Monte Carlo sampling method is used to sample the target weather sequences, categorizing the entire year's target weather sequences into various weather categories. Several weather sequences are then selected from each weather category for atmospheric diffusion calculations. Considering the effects of thermal lift of the plume and building wakes, a modified Gaussian piecewise plume model is used to simulate the diffusion process of released radioactive materials with the atmosphere. That is, based on the sampled target weather sequence data, as well as the plume height and length, plume diffusion and transport calculations are performed to obtain the atmospheric dispersion factor of the ground air below the plume centerline at different distances. By combining the amount of radionuclides released and taking into account factors such as natural decay, dry deposition, and wet deposition during the diffusion process, the ground air concentration and ground deposition concentration below the center line of the radionuclide plume were calculated.

[0056] Please see Figure 3 and Figure 4 , Figure 3 One specific implementation of step S2 is shown. Figure 4 The following is a flowchart of atmospheric diffusion calculation provided in an embodiment of this application, detailed below:

[0057] S21: Obtain the annual hourly meteorological data for the nuclear power plant site and classify the annual hourly meteorological data into various weather categories. S22: Use the Monte Carlo method to perform weather sampling based on each weather category to obtain the target weather sequence. S23: For each target release category and the weather sequence, calculate the time-integrated air concentration and the ground deposition concentration of the radionuclide at each spatial grid point downwind after atmospheric diffusion, based on the nuclide release spectrum.

[0058] Hourly meteorological data for the entire year refers to continuous meteorological observation data recorded hourly in the nuclear power plant site area. This data can be generated using actual meteorological station measurements or numerical simulations, providing comprehensive coverage of meteorological parameter changes across different seasons, day and night, and abrupt weather changes. Weather categories refer to typical weather patterns classified according to key meteorological parameters such as wind speed, wind direction, and atmospheric stability. Cluster analysis can be used to categorize the yearly data into weather types with similar diffusion characteristics, reducing computational complexity and ensuring sampling representativeness. The Monte Carlo method is a probability-based random sampling technique that generates a sequence of random numbers following a probability distribution of weather categories to achieve weather sampling. This method effectively reflects the uncertainty and temporal diversity of meteorological conditions.

[0059] Specifically, by classifying hourly meteorological data throughout the year according to diffusion-related parameters, a set of weather categories with different atmospheric transport characteristics is formed, and a correlation model between meteorological conditions and radioactive diffusion paths is established. The Monte Carlo method is used to randomly sample the occurrence probability of each weather category, generating target weather sequences containing different combinations of meteorological parameters, ensuring that the sampling results statistically cover all possible meteorological evolution processes. For each combination of target release category and sampled weather sequence, based on the type, release rate, and duration of radionuclides in the nuclide release spectrum, combined with plume lift calculations, diffusion parameter corrections, and deposition process simulations, time-integrated air concentrations and ground deposition concentrations are calculated grid-by-grid. This process achieves a probabilistic assessment of the consequences of radioactive diffusion by dynamically coupling release source term characteristics with meteorological transport conditions.

[0060] The time-integral concentration of the Gaussian piecewise plume model, which takes into account factors such as natural decay, dry deposition, and wet deposition during the diffusion process, can be expressed as:

[0061]

[0062] Where C(x,y,z) is the time-integrated activity at (x,y,z), Q is the radionuclide release activity, U is the wind speed at the effective release height, H is the effective release height of the plume, and σ y σ is the atmospheric diffusion parameter in the horizontal direction. z f is the atmospheric diffusion parameter in the vertical direction. d f is the dry sedimentation correction factor. w f is the wet deposition correction factor. R This is the radioactive decay correction factor.

[0063] Specifically, during a radioactive accident, the plume transports radioactive gases and aerosols during its atmospheric diffusion. A Gaussian segmented plume model is used to calculate the atmospheric diffusion of radioactive materials; the calculation process is as follows: Figure 4 As shown. During the calculation, the plume's rise height was obtained based on the heat and height released during the accident; the plume length was calculated hourly based on the plume's release duration and the wind speed at the corresponding time in the sampled target weather sequence. Based on the wind speed and stability data from the sampled representative weather sequence, as well as the plume's height and length data, plume diffusion and transport calculations were performed to obtain the dispersion factor of the ground air below the plume's centerline at different distances. Combining the amount of radionuclides released and considering factors such as natural decay, dry deposition, and wet deposition during the diffusion process, the ground air concentration and ground sediment concentration below the plume's centerline were calculated.

[0064] Specifically, weather sequences are classified according to their impact on early mortality. When calculating multiple plume releases, the release time of the risk-dominant plume is taken as the start time of the weather sequence. If there are plume releases before the risk-dominant plume in the source term, hourly data before the start of the weather sequence are used for the calculation of earlier plumes. A Gaussian plume model is used to calculate downwind atmospheric diffusion. The horizontal and vertical extension of the plume segments are expressed as the horizontal and vertical standard deviations of the normal concentration distribution in the Gaussian plume. It is assumed that the effect of turbulent velocity is much smaller than the mean wind speed, and the initial length of the plume segments is unaffected by diffusion during downwind transport. The plume segment length L (m) is:

[0065]

[0066] Where, Δt i Let the wind speed be v i Release duration; ∑Δt i This refers to the total release duration of the plume segment.

[0067] Please see Figure 5 , Figure 5 A specific implementation of step S23 is shown below:

[0068] S231: For each of the target release categories and the weather sequence, the effective release height of the plume is calculated using the Briggs plume lift formula based on the accident release heat rate in the nuclide release spectrum.

[0069] Please see Figure 6 , Figure 6 A specific implementation of step S231 is shown below:

[0070] S2311: For each target release category and the weather sequence, calculate the buoyancy flux based on the accidental release heat rate in the nuclide release spectrum. S2312: Calculate the plume rise height under neutral unstable conditions based on the buoyancy flux to obtain the first plume rise height, and calculate the plume rise height under stable atmospheric conditions to obtain the second plume rise height. S2313: Obtain the physical release height, and calculate the effective release height based on the physical release height, the first plume rise height, and the second plume rise height.

[0071] Buoyancy flux refers to the upward dynamic parameter of released material per unit time due to temperature differences. Neutral instability refers to a state where the vertical atmospheric temperature gradient is close to the adiabatic lapse rate. Stable atmospheric conditions refer to a state where atmospheric stratification inhibits vertical motion; this can be determined using the Richardson number or temperature gradient threshold, and the corresponding plume rise height calculation model can characterize the inhibitory effect of atmospheric stability on diffusion. Physical release height refers to the vertical distance from the actual emission point of radioactive material to the ground, which can be obtained through the design parameters of nuclear power plant chimneys and serves as the basic parameter for calculating the effective release height.

[0072] In this embodiment, the accidental heat release rate is converted into a buoyancy flux parameter and then input into the plume lift calculation models under neutral and unstable conditions and stable atmospheric conditions, respectively. Under neutral conditions, a lift formula based on the relationship between buoyancy flux and wind speed is used to calculate the first plume lift height; under stable conditions, a modified formula considering atmospheric stratification stability is used to calculate the second plume lift height. The physical release height is used as a baseline parameter and superimposed with the calculation results under the two meteorological conditions, and the smaller value is selected as the effective release height. This calculation method achieves dynamic correction of the release height by distinguishing the differentiated influence of atmospheric stability on plume diffusion.

[0073] Specifically, the thermal plume will rise, and the effective release height of the plume is calculated using the Briggs plume rise formula. No plume rise occurs when the wind speed at release exceeds the critical wind speed (initial motive criterion). Plume rise is also limited by the mixing layer. Initial motive criterion: The Briggs initial motive criterion determines whether the buoyant plume segment can escape the building wake. Only when the wind speed at release is less than the critical wind speed (u... c Only when the plume rises does it occur.

[0074]

[0075] Among them, L p Let F be the length of the plume (i.e., the building height), and F be the buoyancy flux (which depends on ambient atmospheric conditions and the heat release rate (Q), F = 8.97 * 10⁻⁶). 6 Q (where Q is in watts);

[0076] Plume lift equation: Under neutral or unstable weather conditions (stability AD), the first plume lift height is expressed by the following equation:

[0077]

[0078] Where Δh is the height of the first plume; F is the buoyancy flux of the plume lift, m⁴ / s³, taken as 8.97*10 6 Q; Q is the heat release rate; x is the downwind distance; This represents the average wind speed.

[0079] Under stable atmospheric conditions (stability E and F), the rise height of the second plume is expressed by the following formula:

[0080]

[0081] Wherein, the effective release height H = physical release height plus the first plume rise height or the second plume rise height.

[0082] S232: Calculate the initial dimensions of the plume segment, wherein the initial dimensions include initial horizontal diffusion parameters and initial vertical diffusion parameters affected by the building wake.

[0083] Specifically, considering the influence of building wakes, the initial horizontal and vertical diffusion parameters affected by building wakes are calculated as follows:

[0084]

[0085] σ z (t=0)=H b / 2.15

[0086] Among them, W b and H b These are the width and height of the building's wake, respectively.

[0087] A representative weather point is selected to represent the weather conditions of all points along its length, typically the leading edge or midpoint of the plume. The time it takes for any reference point along the length of the plume to reach the downwind cell point is determined by the following formula:

[0088] and

[0089] Where d is the downwind distance from the reactor to the cell point, and Δt d v is the arrival time of the reference point at a distance d; i For the time period Δt i The wind speed; n is the number of time intervals.

[0090] Due to the arrival time t of the leading and trailing edges of the plume segment h and t t The above formula can be used to calculate the exposure time of a person when the smoke plume passes by, which can be calculated by the following formula: Δt e =t t -t h .

[0091] S233: Determine atmospheric diffusion parameters at different downwind distances using the Pasquill-Gifford method.

[0092] S234: Calculate the integrated air concentration for the current period based on the effective release height, the initial size, and the atmospheric diffusion parameters.

[0093] Specifically, during downwind transport, the vertical expansion of a plume is related to ground roughness and limited by the ground and inversion layer, while its lateral expansion along the y-direction is unrestricted. The effective lateral dimension of the plume segment increases with the lateral extension of the plume. Since turbulent velocities are typically small compared to average wind speeds, the horizontal expansion of the plume is negligible. When the plume is not limited by the ground and inversion layer, a Gaussian plume can be expressed as:

[0094]

[0095] Where X(x,y,z) is the time-integrated air concentration at the downwind location (x,y,z); Q is the source strength. σ represents the average wind speed. y σ represents the lateral standard deviation of the smoke plume. z denoted as the longitudinal standard deviation of the plume; h represents the effective release height.

[0096] When the plume expands vertically to a sufficiently large size, it will be confined by the ground and the inversion layer, and the above equations no longer apply. The ground and the inversion layer are treated as totally reflective boundaries. Once the plume is completely mixed vertically, the centerline air concentration is calculated using the simple Gaussian equation:

[0097]

[0098] In the formula, L is the mixing layer height. The atmospheric diffusion parameter σ at different downwind distances is determined using the Pasquill-Gifford method. y and σ z .

[0099] S235: The current time-integrated air concentration is consumed and corrected, and the current time-integrated air concentration is calculated based on the corrected current time-integrated air concentration.

[0100] Specifically, the current time-integrated air concentration is multiplied by the dry deposition correction factor, the wet deposition correction factor, and the radioactive decay correction factor to perform a consumption correction on the current time-integrated air concentration.

[0101] In this embodiment, the Briggs plume rise formula refers to a physical model that calculates the plume rise height using buoyancy flux. Specifically, it can be implemented by combining buoyancy flux with atmospheric stability parameters to accurately reflect the dynamic impact of heat release on plume rise. Initial diffusion parameters refer to the diffusion characteristics of the plume in the near field affected by building wake effects, used to correct for the interference of building structures on the initial diffusion of the plume. The Pasquill-Gifford method is an empirical model that determines the horizontal and vertical diffusion coefficients based on atmospheric stability levels. Specifically, it can use wind speed, cloud cover, and solar radiation parameters from meteorological data to classify stability categories, used to match diffusion patterns under different meteorological conditions. Consumption correction refers to the dynamic decay calculation of air concentration based on dry deposition, wet deposition, and radioactive decay. Specifically, it can be implemented by piecewise integration and superimposing the deposition rate and decay constant, used to reflect the physicochemical changes of nuclides during migration. Path integral refers to discretizing the release process into multiple short time periods and accumulating the concentration contribution along the downwind trajectory. Specifically, it can be achieved using the Lagrange plume segmented tracking method to handle the coupling effect between unsteady release and changes in meteorological conditions.

[0102] Specifically, the effective release height of the plume is calculated using the Briggs plume lift formula. Initial plume diffusion parameters are calculated by incorporating building wake influence coefficients; for example, horizontal diffusion parameters are correlated with building characteristic dimensions, and vertical diffusion parameters are matched to turbulence intensity. Atmospheric diffusion parameters are selected based on Pasquill-Gifford curves; for example, horizontal and vertical diffusion coefficients at specific distances are used under Type D stability conditions. Time-integrated air concentration is calculated using the Gaussian plume formula, where the chimney height is replaced by the effective release height, and diffusion parameters are superimposed with the initial diffusion component. In the consumption correction stage, dry deposition rate, rainfall erosion coefficient, and nuclide half-life corrections are applied to each plume segment. Finally, the total concentration distribution at each grid point is obtained by integrating the concentration contributions of each plume segment along the windward trajectory.

[0103] Further, step S235 includes: performing a consumption correction on the current time-integrated air concentration based on the dry deposition correction coefficient, the wet deposition correction coefficient, and the radioactive decay correction coefficient to generate the corrected current time-integrated air concentration; and calculating the current ground deposition concentration based on the dry deposition rate and the corrected current time-integrated air concentration.

[0104] Specifically, the atmospheric diffusion parameter σ varies under different roughness conditions. z Some adjustments are necessary. The values ​​given by Pasquill-Gifford apply to flat terrain with a roughness z0 = 3 cm.

[0105] The dry deposition correction coefficient is a parameter characterizing the concentration decay of radioactive particulate matter in the atmosphere due to gravitational settling and surface adsorption. It can be calculated using empirical formulas based on surface roughness and vegetation cover, reflecting the impact of different surface features on particulate matter settling. The wet deposition correction coefficient quantifies the efficiency of precipitation scouring in removing radioactive materials from the air. It can be calculated using a correlation model between precipitation intensity and nuclide solubility, simulating the removal effect of aerosol particles during rainfall. The radioactive decay correction coefficient is a correction factor for the decrease in activity due to nuclide decay. It can be calculated using the exponential decay formula based on half-life, dynamically correcting for activity changes in radionuclides during diffusion. The dry deposition rate is the vertical flux parameter of radioactive material migrating from the atmosphere to the surface per unit time. It can be calculated using a correlation model between aerosol particle size distribution and surface roughness, establishing the physical transfer relationship between air concentration and surface deposition.

[0106] Plume depletion considers dry and wet deposition as well as radioactive decay. Dry deposition is determined by surface air concentration and deposition rate, and the amount of dry deposition (ω) is given by the following formula:

[0107] ω(x,y)=v d X(x,y,0)

[0108] Among them, v d It is the dry deposition rate.

[0109] The plume loss (dQ / dx) due to dry deposition is given by the following formula:

[0110]

[0111] The wet sedimentation model, adopted by Brenk and Vogt, is shown below:

[0112]

[0113] Where Λ is the flushing coefficient; I is the rainfall intensity; a, b are dimensionless constants, a = 9.5 * 10 -5 b = 0.8.

[0114] When the plume passes through cell k, the total amount (ΔQk) deposited on the ground in cell k is given by the following formula:

[0115] ΔQ k =Q k [1-f d f w ]

[0116] Where Qk is the amount of aerosol entering cell k, f d For dry sedimentation correction factor and fw Let Gck(y=0) be the wet deposition correction factor. Let Gck(y=0) be the length L. k The average ground concentration of the plume segment below the centerline in cell k is then obtained as follows:

[0117]

[0118] Since the integral is 1, we can obtain

[0119]

[0120] σ y σ z plume height H, average wind speed Given by the following formula:

[0121] σ y,av =0.5[σ y,k +σ y,k+1 ]

[0122] σ z,av =0.5[σ z,k +σ z,k+1 ]

[0123]

[0124] Where k and k+1 represent the values ​​at the entry and exit points of the plume segment, respectively. Therefore, the average plume centerline concentration and ACk (y=0, z=H) can be given by the following formula:

[0125]

[0126] Finally, the gaseous material that remains in the plume after passing through cell k is Q. k+1 =Q k -ΔQ k .

[0127] S236: Divide the release process into multiple short periods, and perform path integration on the current time-integrated air concentration and the current ground deposition concentration for each plume segment. Accumulate the path integrals to obtain the time-integrated air concentration and the ground deposition concentration for each grid point.

[0128] S3: Based on the time-integrated air concentration and the ground deposition concentration, combined with the pre-stored dose conversion factor and the population distribution data of the nuclear power plant site, calculate the individual radiation dose and the collective radiation dose, and perform dose correction on the individual radiation dose and the collective radiation dose according to the protective action data to generate the target individual radiation dose and the target collective radiation dose.

[0129] Specifically, dose assessment, using dose conversion factors provided by dosimetric models, describes the migration of radioactive materials within the human body over time, calculating the radiation dose received by individuals and groups. It calculates the dose received by individuals in the early stages due to external plume exposure, inhalation, ground-deposited external exposure, resuspension exposure, and skin exposure. In the medium to long term, it calculates the dose received by individuals through ground-deposited external exposure, resuspension exposure, ingestion of contaminated food, and ingestion of contaminated drinking water. For ingestion, only the collective dose is calculated. To mitigate public dose, corresponding protective actions are taken at different stages after an accident. The assessment obtains information on the protective actions taken at the target nuclear power plant after a radioactive accident and their triggering conditions. In the early stages, emergency response actions include evacuation, sheltering, and temporary relocation. In the medium to long term, measures include land decontamination, short-term post-decontamination lockdown, permanent closure, and crop disposal. Based on the dose mitigation effect data corresponding to the protective actions, the calculated doses for individuals in the early and medium to long term are corrected, ultimately yielding the radiation dose received by the public under the mitigation effect of the protective actions.

[0130] Please see Figure 7 , Figure 7 A specific implementation of step S3 is shown below:

[0131] S31: For each grid point and each individual group, based on the time-integrated air concentration and the ground deposition concentration, combined with the pre-stored dose conversion factor and the population distribution data of the nuclear power plant site, calculate the dose for all exposure pathways to obtain the initial radiation dose. The initial radiation dose includes the external plume radiation dose, the inhaled internal radiation dose, the ground deposition radiation dose, the resuspension inhalation dose, and the skin deposition radiation dose. S32: Acquire the data corresponding to the protective action to obtain the protective action data, and correct the initial radiation dose based on the protective action data to obtain the corrected radiation dose. S33: Generate the target individual radiation dose and the target group radiation dose based on the corrected radiation dose.

[0132] In this context, grid points refer to dividing the downwind area of ​​a nuclear power plant into several spatial units using spatial discretization methods. This can be achieved using latitude and longitude coordinates or a Cartesian coordinate system, and is used to accurately characterize the spatial distribution characteristics of radionuclides after diffusion. Population groups refer to group categories based on demographic characteristics such as age and gender. This can be achieved using the grouping standards recommended by the International Commission on Radiation Protection (ICRP), and is used to reflect the differences in radiation sensitivity among different populations. The dose conversion factor is the conversion coefficient between a unit radionuclide concentration and the human radiation dose. This can be achieved using the dose coefficient database published by the International Atomic Energy Agency (IAEA), and is used to quantify the dose contribution of different nuclides and different irradiation pathways. The initial radiation dose includes five pathways: external plume radiation dose, inhaled internal radiation dose, resuspension inhalation dose, and skin deposition radiation dose. This can be calculated using the Monte Carlo radiation transport procedure or analytical formulas, and is used to comprehensively cover direct and indirect radiation from radionuclides through airborne propagation and surface deposition. Protective action data includes parameters such as the implementation rate of protective measures, the ratio of indoor to outdoor time spent by personnel, and individual differences in respiratory rate. Specifically, it can be achieved using data from the protective action guidelines in the nuclear emergency response plan, in order to eliminate the deviation between idealized assumptions and actual exposure scenarios.

[0133] In this embodiment, after establishing a spatial grid coordinate system in the downwind area of ​​the nuclear power plant, the external radiation dose during the passage of the plume, the internal radiation dose from inhaling radionuclides in the plume, the secondary dose from inhaling resuspended surface-deposited radionuclides, the radiation dose from direct skin contact with deposited radionuclides, and the continuous radiation dose from skin adsorption of radionuclides are calculated for different age groups and genders within each grid cell. By superimposing the dose contributions of these five radiation pathways, an initial dose distribution without considering protective measures is obtained. Subsequently, correction parameters from actual emergency response scenarios are introduced, such as reducing the external radiation dose based on the shielding effect of surrounding buildings, adjusting the inhaled dose based on the respiratory rate of different age groups, and reducing the number of exposed individuals by combining emergency evacuation ratios. Finally, corrected dose data reflecting the actual exposure conditions is generated. Individual radiation dose is obtained by statistically analyzing the individual radiation doses within each grid point, while the collective radiation dose is calculated by summing the dose contributions of all exposed individuals.

[0134] Specifically, for direct radiation exposure, dose calculation is usually the product of radionuclide concentration, dose conversion factor, exposure duration, and shielding factor.

[0135] The external radiation dose from a radioactive plume can be calculated using the "semi-infinite cloud" method with a finite plume correction factor, as shown in the following formula:

[0136]

[0137] Among them, DCk The external radiation dose received by organ k from the plume; The time-integrated concentration of radionuclide i in the air below the plume centerline; DFC ∞ik denoted as the semi-infinite external plume radiation dose conversion factor for organ k by radionuclide i; C is the finite plume correction factor; F is the irradiation time fraction during plume passage; and SFC is the external plume radiation shielding factor.

[0138] When a plume of smoke passes through, radioactive nuclides can enter the body through respiration. The formula for calculating the inhaled internal radiation dose is as follows:

[0139]

[0140] Among them, DI k AC is the internal radiation dose to organ k caused by the passing of the smoke plume; i The time-integrated ground air concentration of radionuclide i below the plume centerline; DFI ik 1 is the inhaled internal radiation dose conversion factor of radionuclide i to organ k; BR is the respiratory rate; J is the fine cell offset correction factor, which is dimensionless; F is the irradiation time fraction when the plume passes through; SFI is the inhaled internal radiation shielding factor.

[0141] As the plume passes, some radionuclides will be deposited on the ground due to dry deposition, and if there is rainfall, they will also be deposited due to rainwater washing. The radionuclides deposited on the ground will cause external radiation. During the plume's passage, the external radiation dose rate of the radionuclides deposited at time t0 to organ k (i.e., the external radiation dose from ground deposition) is calculated using the following formula:

[0142]

[0143] Among them, GDR k (t0) represents the ground-deposited external irradiation dose rate of organ k at time t0; GC i (t0) represents the ground concentration of radionuclide i deposited below the plume centerline at time t0; DRFC ik is the ground external radiation dose conversion factor for organ k by radionuclide i; J is the fine cell off-center correction factor; SFG is the ground deposition external radiation shielding factor.

[0144] After the plume passes through, the formula for calculating the inhaled internal radiation dose (i.e., the resuspended inhaled dose) of the resuspended radionuclide to organ k is as follows:

[0145]

[0146] Among them, DR k GC represents the resuspension irradiation dose received by organ k. iDRI is the ground concentration of radionuclide i below the center line of the plume when the plume departs. ik 1 is the resuspension dose conversion factor of radionuclide i on organ k; BR is the respiration rate; J is the fine cell off-center correction factor; RF is the time integral resuspension coefficient; SFI is the inhaled internal irradiation shielding factor.

[0147] When the plume passes by, some radionuclides will be deposited on exposed skin via dry deposition, resulting in external irradiation. The formula for calculating the external irradiation dose is:

[0148]

[0149] Where DS represents the external skin irradiation dose; AC i V represents the time-integrated concentration of radionuclide i in the air below the plume centerline; d Dry deposition rate; DFS i is the skin external irradiation dose conversion factor for radionuclide i; J is the fine cell off-center correction factor; F is the irradiation time fraction during plume passage; SFS is the skin external irradiation shielding factor.

[0150] The principle behind the ingestion model in the long-term radiation exposure pathway is that the long-term dose produced by any radionuclide to an organ is the product of (1) the ground concentration of the radionuclide, (2) the combined transfer coefficient of the radionuclide ingested into the human body through this pathway, and (3) the ingestion dose conversion coefficient.

[0151] S4: Calculate the expected number of people with early health effects and the number of people with late health effects based on the target individual radiation dose using a probabilistic model.

[0152] Specifically, by analyzing the relationship between radiation dose to various organs and the probability of somatic effects, a probabilistic model is used to perform quantitative calculations to estimate the number of people expected to experience early and late health effects. It is necessary to calculate both the early and late health effects of radiation exposure on an individual.

[0153] Early health effects include early injury and death, which refer to effects observed after receiving a high acute dose and that occur within days to weeks after irradiation and manifest within days to a year.

[0154] Late-stage health effects include late-stage cancer and death, referring to cancer development and death effects observed within one to several decades after irradiation.

[0155] The probability of early health effects occurring is characterized by the health effects risk factor (r), calculated as follows:

[0156]

[0157] Where r is the average individual health impact risk factor; D is the effective dose to the target organ; D 50 β is the half-effective dose (half of the irradiated population suffers from weakened target organ function or excessive damage to organ combinations leading to death); β is the shape parameter, characterizing the rigidity of the response curve.

[0158] Long-term health effects primarily refer to radiation-induced delayed cancer. The risk of cancer increases rapidly with increasing dose. However, when the dose is large enough to kill cells, further increases in dose result in direct cell death rather than cancerous transformation, thus slowing the increase in cancer risk. The cancer risk below the cell-killing zone exhibits a quadratic relationship with the dose received, while the cancer risk within the cell-killing zone shows a linear relationship. The transition between the quadratic and linear models occurs at 1.5 Sv.

[0159] S5: Calculate the economic loss of personnel caused by the radioactive release accident based on the number of people with early health effects and the number of people with late health effects; calculate the economic loss of materials caused by the radioactive release accident based on the ground deposition concentration and the target individual radiation dose; and calculate the total economic loss based on the economic loss of personnel and the economic loss of materials. The economic loss of personnel includes compensation for personal injury and death and emergency response costs. The economic loss of materials includes decontamination costs, short-term agricultural / non-agricultural blockade costs, agricultural / non-agricultural confiscation fees, evacuation and relocation costs, and crop disposal costs.

[0160] Please see Figure 8 , Figure 8 A specific implementation of step S5 is shown below:

[0161] S51: Obtain the site information of the nuclear power plant, wherein the site information includes population distribution, land distribution, and economic value of agricultural and non-agricultural wealth within a preset range. S52: Calculate the personnel economic loss caused by the radioactive release accident based on the site information, the number of people experiencing early health effects, and the number of people experiencing late health effects. S53: Calculate the material economic loss caused by the radioactive release accident based on the ground deposition concentration, the target individual radiation dose, and the site information. S54: Add the personnel economic loss and the material economic loss to generate the total economic loss.

[0162] Specifically, it is necessary to calculate compensation costs for personal injury and death, emergency evacuation costs, decontamination costs, costs of short-term agricultural / non-agricultural lockdowns, agricultural / non-agricultural confiscation fees, evacuation and relocation costs, and crop disposal costs. Personal injury and death compensation costs are those paid to individuals experiencing health effects during the early and medium-to-long-term phases. Emergency response costs are compensation for evacuation and temporary relocation during the emergency phase, depending on the number of affected people, the scope of evacuation and relocation, etc., including food, accommodation, transportation costs, and income loss incurred during the emergency. Decontamination costs are the expenses incurred during decontamination, the purpose of which is to reduce the radioactivity level in the space to meet long-term habitable dose standards as much as possible. Different decontamination levels and durations correspond to different decontamination costs, which also include the labor costs of decontamination workers. Costs of short-term agricultural / non-agricultural lockdowns can include losses of agricultural / non-agricultural property awaiting restoration of habitability during the short-term lockdown and losses of agricultural / non-agricultural property permanently disabled. Losses of agricultural / non-agricultural property awaiting restoration of habitability during short-term lockdowns: If decontamination is insufficient to restore habitability, a short-term lockdown is required after decontamination to reduce the dose through radioactive decay and weathering. Losses of agricultural / non-agricultural property during a short-term lockdown are the difference between the initial value of the area and its value at the end of the short-term lockdown, taking into account the property's depreciation rate and expected rate of return. Crop disposal costs depend on the local agricultural output, the proportion of milk and crop output, and the disposal time. Losses of agricultural / non-agricultural property permanently decommissioned: If habitability cannot be restored in a cost-effective manner, the area must be permanently decommissioned. In addition to the intrinsic value of the land and property, losses include the costs of permanent relocation, i.e., evacuation and relocation costs. Agricultural / non-agricultural confiscation fees are the agricultural / non-agricultural fees confiscated during the lockdown.

[0163] In one specific embodiment, personal injury compensation is calculated as follows: (Number of early deaths + Number of late deaths + Number of deaths due to health effects such as cancer) * Average compensation standard per person. Emergency response costs are calculated as: Number of affected persons * (Average resettlement cost + Average transportation cost + Average daily income loss * Number of evacuation days). Decontamination costs are calculated as: Contaminated area * Decontamination cost per unit area + Labor cost of decontamination workers. Agricultural product disposal costs are calculated as: Contaminated farmland area * Agricultural product output value per unit area * Disposal period. Loss of permanently prohibited agricultural / non-agricultural property is calculated as: Permanently prohibited area * (Land value + Property value) + Cost of permanent relocation.

[0164] S6: Based on the annual occurrence frequency of the target release category, the annual occurrence frequency of the target weather sequence, and the total economic loss, a risk curve is fitted to obtain an aggregated risk curve.

[0165] Please see Figure 9 , Figure 9 A specific implementation of step S6 is shown below:

[0166] S61: For each radionuclide, a risk curve is fitted based on the annual occurrence frequency of the target release category and the annual occurrence frequency of the target weather sequence according to a preset fitting method, resulting in a single-source term fitting curve, and the single-source term fitting curve is verified. S62: The interval bandwidth and number of intervals are determined based on the upper limit value of the single-source term fitting curve, and the loss value of each source term is output based on the interval bandwidth and the number of intervals. S61: Data scatter points are generated based on the source term loss values, and curve fitting and goodness-of-fact checks are performed based on the data scatter points to generate the aggregated risk curve.

[0167] The single-source-term fitting curve refers to the risk probability distribution curve independently generated for a single radionuclide release source term. This can be achieved by fitting a log-normal distribution or a Weibull distribution model, used to quantify the risk contribution of a single radionuclide under different meteorological conditions. The interval bandwidth refers to the width parameter used to divide the economic loss interval in the aggregated risk curve. This can be dynamically adjusted based on the upper limit of the single-source-term curve, for example, by determining the interval boundary using the quantile method, to balance calculation accuracy and data coverage. The goodness-of-fact test is a statistical analysis method to verify the degree of matching between the aggregated curve and the original data. This can be achieved using the KS test, R-squared fitting, or chi-square test, to ensure the accuracy of the aggregated results in reflecting the superposition effect of multiple sources.

[0168] In this embodiment, multi-source risk data is effectively aggregated through phased processing. First, a single-source risk curve is independently fitted for each radionuclide, ensuring that the release characteristics of different nuclides and the impact of meteorological conditions are modeled separately, and the reliability of the single-source curves is verified through statistical tests. Then, the interval division parameters are dynamically determined based on the upper limit of the loss of the single-source curve, avoiding the neglect or overestimation of low-probability, high-loss events due to fixed interval division. Finally, the loss values ​​of each source term are converted into data scatter points, and a continuous aggregated curve is generated through nonlinear regression or interpolation algorithms. The fitting parameters are then optimized using goodness-of-fact tests to form a risk probability distribution model that comprehensively reflects the superimposed effects of multiple sources.

[0169] Specifically, for the economic loss and probability data of each radioactive source term, a loss risk curve is fitted to obtain a single-source term fitting curve. The preset fitting methods are gamma distribution, Pareto distribution, Weibull distribution, etc., and the goodness of fit is tested using R-squared.

[0170] Based on the upper limit of the fitted loss for each single radioactive source term (m terms, each with a probability of p), select an appropriate bandwidth h and the number of intervals n, and output the loss value for each source term. For example, the loss for source term k (k = 1, 2...10) is h, and the cumulative probabilities corresponding to 2h...nh are pk-1, pk-2...pk-n. The cumulative probability P of the aggregated risk for ten source terms is:

[0171]

[0172] The data scatter points that generate the aggregated risk curve are: (h, P1), (2h, P2), ... (nh, Pn). Based on the above n scatter points, a curve is fitted, and the goodness-of-fit test of R-squared is used to generate the conditional risk curve under the premise of a nuclear damage accident.

[0173] S7: Sample the aggregated risk curve to generate a loss sample set, and perform statistics on the preset indicators based on the loss sample set to generate target risk statistical results.

[0174] Please see Figure 10 , Figure 10 A specific implementation of step S7 is shown below:

[0175] S71: Generate uniformly distributed random numbers in the interval between 0 and 1 using the Monte Carlo method. S72: Use the inverse sampling function to interpolate loss values ​​based on the uniformly distributed random numbers and the aggregated risk curve to generate the loss sample set. S73: Perform statistical analysis on the preset indicators based on the loss sample set to generate the target risk statistical results.

[0176] Among them, the Monte Carlo method refers to a numerical calculation method that simulates probability distribution through random sampling. Specifically, it uses a pseudo-random number generator to generate a uniformly distributed random number sequence in the interval of 0 to 1 to simulate the probability space distribution of risk events, thus providing a probability input basis for subsequent loss value interpolation. The inverse function method refers to a technique that uses the inverse function of the probability distribution function to map uniformly random numbers to actual loss values. Specifically, it uses linear interpolation or spline interpolation methods to perform a reverse search on the cumulative probability distribution curve of the aggregated risk curve, transforming abstract probability values ​​into concrete economic loss values, ensuring that the sampling results accurately reflect the statistical characteristics of the risk curve. Preset indicators refer to a set of economic parameters used to quantify risk, specifically including statistical quantities such as expected loss value, value at risk, and tail conditional expectation. By performing mean calculation, quantile extraction, or conditional probability analysis on the loss sample set, multi-dimensional risk quantification indicators are generated, providing data support for setting insurance liability limits.

[0177] In this embodiment, a large number of uniformly distributed random numbers are first generated using the Monte Carlo method, with each random number corresponding to a probability value of a risk event occurring. Next, each random number is input into the inverse function of the aggregated risk curve for interpolation calculation. For example, when the random number is 0.95, the corresponding loss value is found on the cumulative probability distribution curve; this value represents the maximum possible loss at a 95% confidence level. By repeatedly performing this interpolation process, a sample set containing thousands of loss values ​​is generated, forming a complete loss probability distribution dataset. Finally, statistical analysis is performed on the sample set, such as calculating the average annual loss as the expected loss value, extracting the 95th quantile as the value at risk indicator, and statistically analyzing the expected loss exceeding a specific threshold as a tail risk indicator, thereby outputting multi-dimensional risk quantification results.

[0178] Specifically, the Monte Carlo method generates uniformly distributed random numbers (0, 1), and uses these uniformly distributed random numbers to generate loss random numbers using the inverse function method, typically more than 25,000 times, thereby outputting the following preset parameters of the loss: expected loss value, loss variance, loss value for a given regression period, loss probability for a given loss interval, etc.

[0179] In this embodiment, an accident sequence leading to radioactive release is identified and analyzed based on a two-level probabilistic safety assessment model for nuclear power plants. The annual occurrence frequency of each accident sequence is generated, and the release activity of each radionuclide in the accident sequence is calculated according to a preset release category, resulting in a release category list and a release spectrum for each target release category. Hourly meteorological data for the nuclear power plant site is acquired throughout the year, and target weather sequences are randomly sampled. For each target release category and target weather sequence, the time-integrated air concentration and ground deposition concentration of the radionuclide at each spatial grid point downwind after atmospheric diffusion are calculated based on the release spectrum. Based on the time-integrated air concentration and the ground deposition concentration, combined with pre-stored dose conversion factors and population distribution data of the nuclear power plant site, individual radiation dose and collective radiation dose are calculated. Dose correction is applied to the individual radiation dose and the collective radiation dose based on protective action data to generate target individual radiation dose and target collective radiation dose. A probabilistic model is used as the basis for... The project calculates the expected number of people experiencing early and late health effects based on the target individual radiation dose; calculates the economic losses due to the radioactive release accident based on the number of people experiencing early and late health effects; calculates the material economic losses due to the radioactive release accident based on the ground deposition concentration and the target individual radiation dose; and calculates the total economic loss based on the economic losses of people and the material losses. The economic losses of people include compensation for personal injury and death and emergency response costs; the material economic losses include decontamination costs, short-term agricultural / non-agricultural lockdown costs, agricultural / non-agricultural confiscation fees, evacuation and relocation costs, and crop disposal costs. A risk curve is fitted based on the annual frequency of the target release category, the annual frequency of the target weather sequence, and the total economic loss to obtain an aggregated risk curve. The aggregated risk curve is sampled to generate a loss sample set, and preset indicators are statistically analyzed based on the loss sample set to generate target risk statistical results. This invention integrates a two-level probabilistic safety assessment model, meteorological data simulation, dose calculation model, and economic loss assessment to establish a full-chain quantitative model from radioactive release source items to economic losses. Combined with risk curve fitting technology, it achieves accurate economic quantification of radioactive third-party liability risks. It has the advantages of accurate assessment results, comprehensive coverage of environmental factors, and support for actuarial decision-making in insurance.

[0180] Please refer to Figure 11 As a response to the above Figure 1 To implement the method shown, this application provides an embodiment of a device for economically quantifying the risk of radioactive third-party liability. This device embodiment is similar to... Figure 1 Corresponding to the method embodiments shown, this device can be specifically applied to various electronic devices.

[0181] like Figure 11As shown, the radioactive third-party liability risk economic quantification device of this embodiment includes: a release activity calculation module 81, a concentration calculation module 82, a radiation dose calculation module 83, an effector number calculation module 84, an economic loss calculation module 85, a curve fitting module 86, and a statistical result generation module 87, wherein:

[0182] Release activity calculation module 81 is used to identify and analyze accident sequences that lead to radioactive release based on the secondary probabilistic safety assessment model of nuclear power plants, generate the annual occurrence frequency of each accident sequence, and calculate the release activity of each radionuclide in the accident sequence according to the preset release category, so as to obtain a list of release categories and the release spectrum of radionuclides of each target release category.

[0183] Concentration calculation module 82 is used to acquire hourly meteorological data of the nuclear power plant site throughout the year, randomly sample target weather sequences, and calculate the time integral air concentration and ground deposition concentration of radionuclides at each spatial grid point downwind after atmospheric diffusion based on the nuclide release spectrum for each target release category and the target weather sequence.

[0184] The radiation dose calculation module 83 is used to calculate the individual radiation dose and the collective radiation dose based on the time-integrated air concentration and the ground deposition concentration, combined with the pre-stored dose conversion factor and the population distribution data of the nuclear power plant site, and to perform dose correction on the individual radiation dose and the collective radiation dose according to the protective action data, so as to generate the target individual radiation dose and the target collective radiation dose.

[0185] The effect number calculation module 84 is used to calculate the expected number of early health effects and the number of late health effects based on the target individual radiation dose using a probability model.

[0186] The economic loss calculation module 85 is used to calculate the personnel economic loss caused by the radioactive release accident based on the number of people with early health effects and the number of people with late health effects, to calculate the material economic loss caused by the radioactive release accident based on the ground deposition concentration and the target individual radiation dose, and to calculate the total economic loss based on the personnel economic loss and the material loss. The personnel economic loss includes compensation for personal injury and death and emergency response costs, and the material economic loss includes decontamination costs, agricultural / non-agricultural short-term blockade costs, agricultural / non-agricultural confiscation fees, evacuation and relocation costs, and crop disposal costs.

[0187] The curve fitting module 86 is used to perform risk curve fitting based on the annual occurrence frequency of the target release category, the annual occurrence frequency of the target weather sequence, and the total economic loss to obtain an aggregated risk curve;

[0188] The statistical result generation module 87 is used to sample the aggregated risk curve, generate a loss sample set, and perform statistics on preset indicators based on the loss sample set to generate target risk statistical results.

[0189] Furthermore, the release activity calculation module 81 includes:

[0190] The annual occurrence frequency calculation unit is used to acquire the PSA model data and power plant design parameters of the nuclear power plant, and to identify and analyze the accident based on the power plant design parameters through the secondary probabilistic safety assessment model in order to calculate the annual occurrence frequency of each accident sequence.

[0191] A classification unit is used to classify the accident sequences according to their radioactive release characteristics to obtain release categories, wherein the annual occurrence frequency of each release category is the sum of the frequencies of all accident sequences included in the release category;

[0192] A filtering unit is used to filter the release categories according to a preset filtering rule to obtain a list of release categories, wherein the list of release categories includes multiple target release categories and the annual occurrence frequency of each target release category;

[0193] The total activity statistics unit is used to calculate the total activity of each radionuclide released from the containment into the environment for each target release category using the MAAP procedure, thereby obtaining the nuclide release spectrum for each target release category.

[0194] Furthermore, the concentration calculation module 82 includes:

[0195] The meteorological data acquisition unit is used to acquire the hourly meteorological data of the nuclear power plant site throughout the year and classify the hourly meteorological data of the year into various weather categories;

[0196] A weather sampling unit is used to perform weather sampling based on each of the aforementioned weather categories using the Monte Carlo method to obtain the target weather sequence;

[0197] The concentration statistics unit is used to calculate, based on the nuclide release spectrum, the time-integrated air concentration and the ground deposition concentration of the radionuclide at each spatial grid point downwind after atmospheric diffusion for each of the target release categories and the weather sequence.

[0198] Furthermore, the concentration statistics unit includes:

[0199] An effective release height calculation unit is used to calculate the effective release height of a plume based on the accidental release heat rate in the nuclide release spectrum and the weather sequence for each of the target release categories and the weather sequence, using the Briggs plume lifting formula.

[0200] An initial size calculation unit is used to calculate the initial size of the plume segment, wherein the initial size includes initial diffusion parameters in the horizontal direction and initial diffusion parameters in the vertical direction, which are affected by the building wake.

[0201] The atmospheric diffusion parameter determination unit is used to determine atmospheric diffusion parameters at different downwind distances according to the Pasquill-Gifford method.

[0202] An integral air concentration calculation unit is used to calculate the integral air concentration for the current period of time based on the effective release height, the initial size, and the atmospheric diffusion parameters.

[0203] The ground deposition concentration calculation unit is used to perform consumption correction on the current time-integrated air concentration and calculate the current time-integrated air concentration based on the corrected current time-integrated air concentration.

[0204] The path integral unit is used to divide the release process into multiple short time periods, and to perform path integral on the current time integral air concentration and the current ground deposition concentration for each plume segment. The path integrals are then accumulated to obtain the time integral air concentration and the ground deposition concentration for each grid point.

[0205] Furthermore, effectively freeing up the height computing unit includes:

[0206] A buoyancy flux calculation unit is used to calculate the buoyancy flux for each of the target release categories and the weather sequence, based on the accident release heat rate in the nuclide release spectrum.

[0207] The plume lift height calculation unit is used to calculate the plume lift height under neutral and unstable conditions based on the buoyancy flux to obtain the first plume lift height, and to calculate the plume lift height under stable atmospheric conditions to obtain the second plume lift height.

[0208] The height calculation unit is used to obtain the physical release height and calculate the effective release height based on the physical release height, the first plume rise height, and the second plume rise height.

[0209] Furthermore, the surface sediment concentration calculation unit includes:

[0210] The correction unit is used to perform consumption correction on the current time-integrated air concentration based on the dry deposition correction coefficient, wet deposition correction coefficient, and radioactive decay correction coefficient, and generate the corrected current time-integrated air concentration.

[0211] The current segment ground sediment concentration calculation unit is used to calculate the current segment ground sediment concentration based on the dry deposition rate and the corrected current segment time integral air concentration.

[0212] Furthermore, the radiation dose calculation module 83 includes:

[0213] The initial radiation dose calculation unit is used to calculate the dose of all irradiation pathways for each grid point and each population group based on the time-integrated air concentration and the ground deposition concentration, combined with the pre-stored dose conversion factor and the population distribution data of the nuclear power plant site, to obtain the initial radiation dose, wherein the initial radiation dose includes the external plume irradiation dose, the inhaled internal irradiation dose, the ground deposition irradiation dose, the resuspension inhalation dose, and the skin deposition irradiation dose;

[0214] A radiation dose correction unit is used to acquire data corresponding to the protective action, obtain the protective action data, and correct the initial radiation dose based on the protective action data to obtain the corrected radiation dose.

[0215] A collective radiation dose generation unit is used to generate the target individual radiation dose and the target collective radiation dose based on the modified radiation dose.

[0216] Furthermore, the economic loss calculation module 85 includes:

[0217] The site information acquisition unit is used to acquire the site information of the nuclear power plant, wherein the site information includes population distribution, land distribution, and economic value of agricultural and non-agricultural wealth within a preset range;

[0218] The personnel economic loss calculation unit is used to calculate the personnel economic loss caused by the radioactive release accident based on the plant site information, the number of people with early health effects, and the number of people with late health effects.

[0219] The material economic loss calculation unit is used to calculate the material economic loss caused by the radioactive release accident based on the ground deposition concentration, the target individual radiation dose, and the plant site information.

[0220] The total economic loss calculation unit is used to add the personnel economic loss and the material economic loss to generate the total economic loss.

[0221] Furthermore, the curve fitting module 86 includes:

[0222] The single-source fitting curve generation unit is used to fit a risk curve for each radionuclide based on the annual occurrence frequency of the target release category and the annual occurrence frequency of the target weather sequence according to a preset fitting method, to obtain a single-source fitting curve, and to verify the single-source fitting curve.

[0223] The source term loss value output unit is used to determine the interval bandwidth and the number of intervals based on the upper limit of the single source term fitting curve, and output the loss value of each source term based on the interval bandwidth and the number of intervals.

[0224] The aggregation risk curve generation unit is used to generate data scatter points based on the source term loss value, and to perform curve fitting and goodness test based on the data scatter points to generate the aggregation risk curve.

[0225] Furthermore, the statistical results generation module 87 includes:

[0226] Uniformly distributed random number generation unit, used to generate uniformly distributed random numbers in the interval 0 to 1 using the Monte Carlo method;

[0227] The loss sample set generation unit is used to sample the inverse function and interpolate the loss value based on the uniformly distributed random number and the aggregated risk curve to generate the loss sample set.

[0228] The risk statistics unit is used to perform statistics on the preset indicators based on the loss sample set and generate the target risk statistics results.

[0229] To address the aforementioned technical problems, embodiments of this application also provide a computer device. Please refer to [link / reference needed]. Figure 12 , Figure 12 This is a basic structural block diagram of the computer device in this embodiment.

[0230] Computer device 9 includes a memory 91, a processor 92, and a network interface 93 that are interconnected via a system bus. It should be noted that... Figure 12 Only a computer device 9 with three components—memory 91, processor 92, and network interface 93—is shown. It should be understood that implementing all shown components is not required; more or fewer components may be implemented alternatively. Those skilled in the art will understand that the computer device described herein is a device capable of automatically performing numerical calculations and / or information processing according to pre-set or stored instructions. Its hardware includes, but is not limited to, microprocessors, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), digital signal processors (DSPs), embedded devices, etc.

[0231] Computer devices can include desktop computers, laptops, handheld computers, and cloud servers. These devices allow for human-computer interaction with users through keyboards, mice, remote controls, touchpads, or voice-activated devices.

[0232] The memory 91 includes at least one type of readable storage medium, including flash memory, hard disk, multimedia card, card-type memory (e.g., SD or DX memory), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic memory, magnetic disk, optical disk, etc. In some embodiments, the memory 91 may be an internal storage unit of the computer device 9, such as the hard disk or memory of the computer device 9. In other embodiments, the memory 91 may also be an external storage device of the computer device 9, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on the computer device 9. Of course, the memory 91 may also include both internal storage units and external storage devices of the computer device 9. In this embodiment, the memory 91 is typically used to store the operating system and various application software installed on the computer device 9, such as the program code for the economic quantification method of radioactive third-party liability risk. In addition, the memory 91 can also be used to temporarily store various types of data that have been output or will be output.

[0233] In some embodiments, processor 92 may be a central processing unit (CPU), controller, microcontroller, microprocessor, or other data processing chip. This processor 92 is typically used to control the overall operation of computer device 9. In this embodiment, processor 92 is used to run program code stored in memory 91 or process data, for example, to run the program code of the above-described method for economically quantifying the risk of third-party liability in radioactive materials, to implement various embodiments of the method.

[0234] The network interface 93 may include a wireless network interface or a wired network interface, which is typically used to establish communication connections between the computer device 9 and other electronic devices.

[0235] This application also provides another embodiment, namely, a computer-readable storage medium storing a computer program that can be executed by at least one processor to cause the at least one processor to perform the steps of the above-described method for economically quantifying the risk of radioactive third-party liability.

[0236] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods of the various embodiments of this application.

[0237] Obviously, the embodiments described above are merely some embodiments of this application, not all embodiments. The accompanying drawings show preferred embodiments of this application, but do not limit the scope of this application. This application can be implemented in many different forms; rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing specific embodiments, or make equivalent substitutions for some of the technical features. Any equivalent structures made using the content of this application's specification and drawings, directly or indirectly applied to other related technical fields, are similarly within the scope of protection of this application.

Claims

1. A method for economically quantifying the risk of liability for radioactive third parties, characterized in that, include: Based on the two-level probabilistic safety assessment model of nuclear power plants, the accident sequences that lead to radioactive release are identified and analyzed, the annual occurrence frequency of each accident sequence is generated, and the release activity of each radionuclide in the accident sequence is calculated according to the preset release category, so as to obtain a list of release categories and the release spectrum of radionuclides of each target release category. Acquire hourly meteorological data for the nuclear power plant site throughout the year, randomly sample target weather sequences, and calculate the time-integrated air concentration and ground deposition concentration of radionuclides at each spatial grid point downwind after atmospheric diffusion based on the nuclide release spectrum for each target release category and the target weather sequence. Based on the time-integrated air concentration and the ground deposition concentration, combined with the pre-stored dose conversion factor and the population distribution data of the nuclear power plant site, the individual radiation dose and the collective radiation dose are calculated, and the individual radiation dose and the collective radiation dose are corrected according to the protective action data to generate the target individual radiation dose and the target collective radiation dose. A probabilistic model was used to calculate the expected number of people experiencing early and late health effects based on the target individual radiation dose; The economic losses due to the radioactive release accident are calculated based on the number of people with early health effects and the number of people with late health effects. The material economic losses due to the radioactive release accident are calculated based on the ground deposition concentration and the target individual radiation dose. The total economic losses are calculated based on the economic losses due to personnel and the material losses. The economic losses due to personnel include compensation for personal injury and death and emergency response costs. The material economic losses include decontamination costs, agricultural / non-agricultural short-term blockade costs, agricultural / non-agricultural confiscation fees, evacuation and relocation costs, and crop disposal costs. Based on the annual frequency of the target release category, the annual frequency of the target weather sequence, and the total economic loss, a risk curve is fitted to obtain an aggregated risk curve. The aggregated risk curve is sampled to generate a loss sample set, and the preset indicators are statistically analyzed based on the loss sample set to generate target risk statistical results.

2. The method for economically quantifying the risk of radioactive third-party liability according to claim 1, characterized in that, The nuclear power plant-based secondary probabilistic safety assessment model identifies and analyzes accident sequences leading to radioactive releases, generates the annual occurrence frequency of each accident sequence, and calculates the release activity of each radionuclide in the accident sequence according to a preset release category, obtaining a list of release categories and the release spectrum of radionuclides for each target release category, including: The PSA model data and plant design parameters of the nuclear power plant are obtained, and the two-level probabilistic safety assessment model is used to identify and analyze the accident based on the plant design parameters in order to calculate the annual occurrence frequency of each accident sequence. The accident sequences are classified according to their radioactive release characteristics to obtain release categories, wherein the annual occurrence frequency of each release category is the sum of the frequencies of all accident sequences contained in the release category; The release categories are filtered according to preset filtering rules to obtain a list of release categories, wherein the list of release categories includes multiple target release categories and the annual occurrence frequency of each target release category; For each target release category, the total activity of each radionuclide released from the containment into the environment is obtained using the MAAP procedure to obtain the nuclide release spectrum for each target release category.

3. The method for economically quantifying the risk of radioactive third-party liability according to claim 1, characterized in that, The process of acquiring hourly meteorological data for the nuclear power plant site throughout the year, randomly sampling target weather sequences, and calculating the time-integrated air concentration and ground deposition concentration of radionuclides at each spatial grid point downwind after atmospheric diffusion based on the nuclide release spectrum for each target release category and target weather sequence includes: Obtain the annual hourly meteorological data for the nuclear power plant site, and classify the annual hourly meteorological data into various weather categories; The target weather sequence is obtained by performing weather sampling based on each of the aforementioned weather categories using the Monte Carlo method. For each target release category and the weather sequence, the time-integrated air concentration and the ground deposition concentration of the radionuclide at each spatial grid point downwind after atmospheric diffusion are calculated based on the radionuclide release spectrum.

4. The method for economically quantifying the risk of radioactive third-party liability according to claim 3, characterized in that, The calculation of the time-integrated air concentration and the ground deposition concentration of the radionuclide at each spatial grid point downwind after atmospheric diffusion, based on the radionuclide release spectrum for each target release category and the weather sequence, includes: For each target release category and the weather sequence, the effective release height of the plume is calculated using the Briggs plume lift formula based on the accidental release heat rate in the nuclide release spectrum. Calculate the initial dimensions of the plume segment, wherein the initial dimensions include initial horizontal diffusion parameters and initial vertical diffusion parameters affected by the building wake; Atmospheric diffusion parameters at different downwind distances were determined using the Pasquill-Gifford method. Calculate the integrated air concentration for the current period based on the effective release height, the initial size, and the atmospheric diffusion parameters; The current time-integrated air concentration is adjusted for consumption, and the current time-integrated air concentration is calculated based on the adjusted current time-integrated air concentration. The release process is divided into multiple short periods, and the time-integrated air concentration and the ground deposition concentration corresponding to the current period are path-integrated for each plume segment. The path integrals are accumulated to obtain the time-integrated air concentration and the ground deposition concentration for each grid point.

5. The method for economically quantifying the risk of radioactive third-party liability according to claim 4, characterized in that, For each of the target release categories and the weather sequence, the effective release height of the plume is calculated using the Briggs plume lift formula based on the accidental release heat rate in the nuclide release spectrum, including: For each target release category and the weather sequence, the buoyancy flux is calculated based on the accidental heat release rate in the nuclide release spectrum; The first plume rise height is obtained by calculating the plume rise height under neutral and unstable conditions based on the buoyancy flux, and the second plume rise height is obtained by calculating the plume rise height under stable atmospheric conditions. Obtain the physical release height, and calculate the effective release height based on the physical release height, the first plume rise height, and the second plume rise height.

6. The method for economically quantifying the risk of radioactive third-party liability according to claim 4, characterized in that, The step of adjusting the current time-integrated air concentration by consumption and calculating the current time-integrated air concentration based on the adjusted concentration includes: The current time-integrated air concentration is consumed and corrected based on the dry deposition correction factor, wet deposition correction factor, and radioactive decay correction factor to generate the corrected current time-integrated air concentration. The current segment ground deposition concentration is calculated based on the dry deposition rate and the corrected integrated air concentration for the current segment.

7. The method for economically quantifying the risk of radioactive third-party liability according to claim 1, characterized in that, The calculation of individual and collective radiation doses based on the time-integrated air concentration and the ground deposition concentration, combined with pre-stored dose conversion factors and population distribution data of the nuclear power plant site, and dose correction of the individual and collective radiation doses based on protective action data, to generate target individual and target collective radiation doses, includes: For each grid point and each person group, based on the time-integrated air concentration and the ground deposition concentration, combined with the pre-stored dose conversion factor and the population distribution data of the nuclear power plant site, the dose of all irradiation pathways is calculated to obtain the initial radiation dose, wherein the initial radiation dose includes the external plume irradiation dose, the inhaled internal irradiation dose, the ground deposition irradiation dose, the resuspension inhalation dose, and the skin deposition irradiation dose; Obtain the data corresponding to the protective action, obtain the protective action data, and correct the initial radiation dose based on the protective action data to obtain the corrected radiation dose; The target individual radiation dose and the target collective radiation dose are generated based on the corrected radiation dose.

8. The method for economically quantifying the risk of radioactive third-party liability according to claim 1, characterized in that, The calculation of personnel economic losses due to the radioactive release accident based on the number of people with early health effects and the number of people with late health effects, the calculation of material economic losses due to the radioactive release accident based on the ground deposition concentration and the target individual radiation dose, and the calculation of total economic losses based on the personnel economic losses and the material losses, include: Obtain the site information of the nuclear power plant, wherein the site information includes population distribution, land distribution, and economic value of agricultural and non-agricultural wealth within a preset range; Calculate the economic losses to personnel caused by the radioactive release accident based on the plant site information, the number of people with early health effects, and the number of people with late health effects; The economic losses of materials caused by the radioactive release accident are calculated based on the ground deposition concentration, the target individual radiation dose, and the plant site information. The total economic loss is generated by adding the personnel economic loss and the material economic loss together.

9. The method for economically quantifying the risk of radioactive third-party liability according to any one of claims 1 to 8, characterized in that, The risk curve is obtained by fitting a risk curve based on the annual frequency of the target release category, the annual frequency of the target weather sequence, and the total economic loss, including: For each radionuclide, a risk curve is fitted based on the annual occurrence frequency of the target release category and the annual occurrence frequency of the target weather sequence according to a preset fitting method to obtain a single-source fitting curve, and the single-source fitting curve is then tested. The interval bandwidth and number of intervals are determined based on the upper limit of the single-source-term fitting curve, and the loss value of each source term is output based on the interval bandwidth and the number of intervals. Data scatter points are generated based on the source term loss values, and curve fitting and goodness-of-fact testing are performed based on the data scatter points to generate the aggregated risk curve.

10. The method for economically quantifying the risk of radioactive third-party liability according to any one of claims 1 to 8, characterized in that, The step of sampling the aggregated risk curve to generate a loss sample set, and then statistically analyzing preset indicators based on the loss sample set to generate target risk statistical results includes: The Monte Carlo method is used to generate uniformly distributed random numbers in the interval between 0 and 1. The sampling inverse function interpolates the loss values ​​based on the uniformly distributed random numbers and the aggregated risk curve to generate the loss sample set; The preset indicators are statistically analyzed based on the loss sample set to generate the target risk statistical results.

11. A device for economically quantifying the risk of liability for radioactive third parties, characterized in that, include: The release activity calculation module is used to identify and analyze accident sequences that lead to radioactive release based on the secondary probabilistic safety assessment model of nuclear power plants, generate the annual occurrence frequency of each accident sequence, and calculate the release activity of each radionuclide in the accident sequence according to the preset release category, so as to obtain a list of release categories and the release spectrum of radionuclides of each target release category. The concentration calculation module is used to acquire hourly meteorological data of the nuclear power plant site throughout the year, randomly sample target weather sequences, and calculate the time integral air concentration and ground deposition concentration of radionuclides at each spatial grid point downwind after atmospheric diffusion based on the nuclide release spectrum for each target release category and the target weather sequence. The radiation dose calculation module is used to calculate individual radiation dose and collective radiation dose based on the time-integrated air concentration and the ground deposition concentration, combined with pre-stored dose conversion factors and population distribution data of the nuclear power plant site, and to perform dose correction on the individual radiation dose and the collective radiation dose according to the protective action data, so as to generate target individual radiation dose and target collective radiation dose. The effect number calculation module is used to calculate the expected number of early health effects and the number of late health effects based on the target individual radiation dose using a probability model. The economic loss calculation module is used to calculate the personnel economic loss caused by the radioactive release accident based on the number of people with early health effects and the number of people with late health effects, to calculate the material economic loss caused by the radioactive release accident based on the ground deposition concentration and the target individual radiation dose, and to calculate the total economic loss based on the personnel economic loss and the material loss. The personnel economic loss includes compensation for personal injury and death and emergency response costs, and the material economic loss includes decontamination costs, agricultural / non-agricultural short-term blockade costs, agricultural / non-agricultural confiscation fees, evacuation and relocation costs, and crop disposal costs. The curve fitting module is used to fit a risk curve based on the annual occurrence frequency of the target release category, the annual occurrence frequency of the target weather sequence, and the total economic loss, to obtain an aggregated risk curve. The statistical results generation module is used to sample the aggregated risk curve, generate a loss sample set, and perform statistics on preset indicators based on the loss sample set to generate target risk statistical results.

12. The device for economically quantifying the risk of radioactive third-party liability according to claim 11, characterized in that, The release activity calculation module includes: The annual occurrence frequency calculation unit is used to acquire the PSA model data and power plant design parameters of the nuclear power plant, and to identify and analyze the accident based on the power plant design parameters through the secondary probabilistic safety assessment model in order to calculate the annual occurrence frequency of each accident sequence. A classification unit is used to classify the accident sequences according to their radioactive release characteristics to obtain release categories, wherein the annual occurrence frequency of each release category is the sum of the frequencies of all accident sequences included in the release category; A filtering unit is used to filter the release categories according to a preset filtering rule to obtain a list of release categories, wherein the list of release categories includes multiple target release categories and the annual occurrence frequency of each target release category; The total activity statistics unit is used to calculate the total activity of each radionuclide released from the containment into the environment for each target release category using the MAAP procedure, thereby obtaining the nuclide release spectrum for each target release category.

13. The device for economically quantifying the risk of radioactive third-party liability according to claim 11, characterized in that, The concentration calculation module includes: The meteorological data acquisition unit is used to acquire the hourly meteorological data of the nuclear power plant site throughout the year and classify the hourly meteorological data of the year into various weather categories; A weather sampling unit is used to perform weather sampling based on each of the aforementioned weather categories using the Monte Carlo method to obtain the target weather sequence; The concentration statistics unit is used to calculate, based on the nuclide release spectrum, the time-integrated air concentration and the ground deposition concentration of the radionuclide at each spatial grid point downwind after atmospheric diffusion for each of the target release categories and the weather sequence.

14. A computer device, characterized in that, It includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the method for economic quantification of radioactive third-party liability risk as described in any one of claims 1 to 10.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method for economically quantifying the risk of radioactive third-party liability as described in any one of claims 1 to 10.

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