Method and apparatus for deconvoluting neutron spectra

Abstract

The application provides a neutron spectrum unfolding method and device, and relates to the field of reactors. The method comprises the following steps: obtaining a theoretical neutron spectrum of a neutron source at a target position after the neutron source passes through M media; obtaining N neutron spectrum response functions corresponding to N detectors respectively; extracting N characteristic basis functions based on the theoretical neutron spectrum; determining expansion coefficients corresponding to each characteristic basis function according to readings of each detector, the neutron spectrum response functions corresponding to each detector, and the N characteristic basis functions; and determining a sum value of a product of each characteristic basis function and the expansion coefficient corresponding to the characteristic basis function as a target neutron spectrum at the target position under the action of the neutron source. In this way, when the characteristic basis functions are extracted based on the theoretical neutron spectrum, the number of the characteristic basis functions is equal to the number of the detectors, a unique solution of the neutron spectrum can be obtained by solving, the occurrence of an underdetermined problem is avoided, and the accuracy of the spectrum unfolding result is improved.

Description

Technical Field

[0001] This invention relates to the field of reactors, and more specifically to a method and apparatus for interpreting neutron energy spectra. Background Technology

[0002] The neutron energy spectrum, which is the distribution of neutron flux density with energy, is a key parameter in reactor core design and therefore typically needs to be verified through measurements from reactor physics experiments. In general energy spectrum measurement methods, the neutron energy spectrum cannot be obtained directly; it must be derived from the measured values ​​by interpreting the spectrum using the detection response function of a detector system.

[0003] Existing spectral analysis methods, such as generalized least squares (GLS), are prone to overdetermined or underdetermined problems. On the one hand, GLS has limited adaptability to ill-conditioned matrix problems, and the results tend to exhibit oscillations. On the other hand, the accuracy of GLS solutions is highly dependent on the initial values ​​of the iterations. Therefore, the results of existing spectral analysis methods are not stable or accurate enough, and their applicability to the problem needs to be expanded. Summary of the Invention

[0004] The purpose of this application is to provide a method and apparatus for interpreting neutron energy spectra, so that the interpretation results are unique and the accuracy is improved.

[0005] In a first aspect, embodiments of this application provide a neutron energy spectrum interpretation method, applied to an interpretation device. The interpretation device includes N detectors, each detector being used to measure the neutron energy spectrum at the target position after the neutron source has passed through M media; N and M are both positive integers.

[0006] This spectral interpretation method includes:

[0007] Obtain the theoretical neutron energy spectrum at the target location after the neutron source passes through M media;

[0008] Obtain the neutron energy spectrum response functions corresponding to N detectors;

[0009] N characteristic basis functions are extracted based on theoretical neutron energy spectrum;

[0010] Based on the readings of each detector, the corresponding neutron energy spectrum response function of each detector, and N characteristic basis functions, determine the expansion coefficients corresponding to each characteristic basis function;

[0011] The sum of the products of each characteristic basis function and its corresponding expansion coefficient is determined as the target neutron energy spectrum at the target location under the influence of the neutron source.

[0012] In some implementations, obtaining the theoretical neutron energy spectrum at the target location after the neutron source has passed through M media includes:

[0013] Obtain the first theoretical neutron energy spectrum and the second theoretical neutron energy spectrum; the first theoretical neutron energy spectrum is the theoretical neutron energy spectrum at the target position after the neutron source passes through M media under optimal operating conditions, and the second theoretical neutron energy spectrum includes I theoretical neutron energy spectra at the target position after the neutron source passes through M media under I sets of perturbation operating conditions, where I is a positive integer.

[0014] In some implementations, obtaining the first theoretical neutron energy spectrum includes:

[0015] Obtain the optimal values ​​of each parameter for M media;

[0016] Based on the optimal value, the neutron energy spectrum of the first theory is determined.

[0017] In some implementations, obtaining the second theoretical neutron energy spectrum includes:

[0018] Obtain the optimal values ​​and error values ​​of each parameter for M media;

[0019] For each parameter in M ​​media, the sum of the optimal value of the parameter and the error is determined as the upper limit of the parameter, and the difference between the optimal value of the parameter and the error of the parameter is determined as the lower limit of the parameter.

[0020] Determine I parameter combinations corresponding to M media; each parameter combination includes the target value of each parameter in the M media; the target value of each parameter is any value between the upper limit and the lower limit of the parameter; at least one parameter in each parameter combination has a different target value;

[0021] Based on I combinations of parameters, I second theoretical neutron energy spectra are determined.

[0022] In some implementations, N characteristic basis functions are extracted based on the theoretical neutron energy spectrum, including:

[0023] Construct the matrix of the theoretical energy spectrum based on the theoretical neutron energy spectrum;

[0024] The matrix is ​​decomposed to obtain N characteristic basis functions.

[0025] In some implementations, the expansion coefficients corresponding to each characteristic basis function are determined based on the readings of each detector, the neutron energy spectrum response function corresponding to each detector, and N characteristic basis functions, including:

[0026] By substituting the readings of each detector, the corresponding neutron energy spectrum response function of each detector, and the N characteristic basis functions into the target formula, the expansion coefficients corresponding to each characteristic basis function are obtained.

[0027] The objective formula is:

[0028]

[0029] Among them, C n R represents the reading of the nth detector. n (E g ) represents the neutron energy spectrum response function corresponding to the nth detector, φ k (E g ) represents the k-th characteristic basis function, a k denoted by , where represents the expansion coefficient corresponding to the k-th characteristic basis function, N represents the number of detectors, and G represents the number of energy groups in the neutron energy spectrum response function; the values ​​of n range from 1 to N, the values ​​of k range from 1 to N, and the values ​​of g range from 1 to G.

[0030] Secondly, embodiments of this application provide a neutron energy spectrum interpretation device, which is applied to a spectral interpretation equipment. The spectral interpretation equipment includes N detectors, each detector being used to measure the neutron energy spectrum at the target position after the neutron source has passed through M media; N and M are both positive integers.

[0031] The spectrum interpretation device includes:

[0032] The first acquisition module is used to acquire the theoretical neutron energy spectrum at the target position after the neutron source has passed through M media;

[0033] The second acquisition module is used to acquire the neutron energy spectrum response functions corresponding to the N detectors respectively;

[0034] The extraction module is used to extract N characteristic basis functions based on the theoretical neutron energy spectrum;

[0035] The first determining module is used to determine the expansion coefficients corresponding to each characteristic basis function based on the readings of each detector, the neutron energy spectrum response function corresponding to each detector, and N characteristic basis functions.

[0036] The second determining module is used to determine the sum of the products of each characteristic basis function and its corresponding expansion coefficient as the target neutron energy spectrum at the target location under the action of the neutron source.

[0037] Thirdly, embodiments of this application provide a spectrum interpretation device, including:

[0038] The memory is configured to store instructions; and

[0039] The processor is configured to retrieve the instructions from the memory and, when executing the instructions, to implement the neutron energy spectrum descaling method provided in the first aspect of the embodiments of this application.

[0040] Fourthly, embodiments of this application provide a machine-readable storage medium storing instructions that cause a machine to execute the neutron energy spectrum interpretation method described above.

[0041] Fifthly, embodiments of this application provide a computer program product in which instructions, when executed by the processor of a spectrum decomposition device, cause the spectrum decomposition device to perform the neutron energy spectrum decomposition method described above.

[0042] In this embodiment, the theoretical neutron energy spectrum of the neutron source at the target location after passing through M media is obtained; the neutron energy spectrum response functions corresponding to N detectors are obtained; N characteristic basis functions are extracted based on the theoretical neutron energy spectrum; the expansion coefficients corresponding to each characteristic basis function are determined according to the readings of each detector, the corresponding neutron energy spectrum response function of each detector, and the N characteristic basis functions; the sum of the products of each characteristic basis function and its corresponding expansion coefficient is determined as the target neutron energy spectrum at the target location under the influence of the neutron source. Thus, when extracting characteristic basis functions based on the theoretical neutron energy spectrum, the number of characteristic basis functions is made equal to the number of detectors, and a unique solution to the neutron energy spectrum can be obtained through solving, avoiding the underdetermined problem and improving the accuracy of the spectral results. Attached Figure Description

[0043] Figure 1 This is one of the flowcharts illustrating the neutron energy spectrum interpretation method provided in the embodiments of this application;

[0044] Figure 2 This is a schematic diagram of neutron energy spectrum acquisition under perturbation state provided in an embodiment of this application;

[0045] Figure 3 This is a second schematic flowchart of the neutron energy spectrum interpretation method provided in the embodiments of this application;

[0046] Figure 4 This is a schematic diagram of the neutron energy spectrum interpretation device provided in the embodiments of this application;

[0047] Figure 5 This is a schematic diagram of the structure of the spectrum interpretation device provided in the embodiments of this application. Detailed Implementation

[0048] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0049] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0050] The following description, in conjunction with the accompanying drawings, details the neutron energy spectrum interpretation method and apparatus provided in this application through specific embodiments and application scenarios.

[0051] Please see Figure 1 This is one of the flowcharts illustrating a neutron energy spectrum interpretation method provided in this application embodiment. This method is applied to a spectral interpretation device. Please refer to... Figure 2 This is a schematic diagram of neutron energy spectrum acquisition under perturbed conditions provided in an embodiment of this application, as shown below. Figure 2 As shown, the spectral analysis device includes N detectors, each used to measure the neutron energy spectrum at the target location after the neutron source has passed through M media; where N and M are both positive integers. The detectors measure the neutron energy spectrum at the target location after the neutron source has passed through M media.

[0052] In this embodiment of the application, the number of detectors can be multiple.

[0053] like Figure 1 As shown, the spectral interpretation method includes the following steps S100 to S500.

[0054] Step S100: Obtain the theoretical neutron energy spectrum at the target location after the neutron source has passed through M media.

[0055] In this embodiment, a neutron source can be understood as a device that generates neutrons, including a dedicated neutron generation device or neutrons generated spontaneously by fuel. A medium can be understood as the interaction medium between neutrons and the matter or material through which they pass. The medium can include, but is not limited to, gases, liquids, solids, and other materials, with the aim of influencing and altering the energy distribution, propagation mode, and interaction with the detector of neutrons, thereby affecting the neutron energy spectrum at the target location. The neutron energy spectrum can be understood as the energy distribution of the neutron flux density. The target location can be understood as the location of the neutron energy spectrum to be measured, and can be specifically set according to actual conditions.

[0056] In the embodiments of this application, there may be one neutron source or a combination of multiple sources. The location of the neutron source may or may not overlap with that of the medium.

[0057] In this embodiment, M media may exist between the detector and the neutron source. The detector can be used to measure the neutron energy spectrum at the target location after the neutron source passes through the M media. The number of detectors can be N, where N and M are both positive integers.

[0058] Step S200: Obtain the neutron energy spectrum response functions corresponding to the N detectors respectively.

[0059] In this embodiment of the application, for N detectors, the neutron energy spectrum response function of each detector is R. n (E g ), n = 1, 2, ..., N, g = 1, 2, ..., G, where G is the energy group number of the response function, typically several hundred. The neutron energy spectrum response function characterizes the conversion relationship between the neutron energy spectrum and the detector signal. E can be understood as the neutron energy, E g It can represent the energy value of the neutron corresponding to the energy group number of the response function.

[0060] In the embodiments of this application, there are no restrictions on the type of detector or the type of neutron energy spectrum to be measured.

[0061] Step S300: Extract N characteristic basis functions based on the theoretical neutron energy spectrum.

[0062] In this embodiment of the application, the theoretical neutron energy spectrum may include one type of neutron energy spectrum or two types of neutron energy spectra. In one example, the theoretical neutron energy spectrum may include a first theoretical neutron energy spectrum and a second theoretical neutron energy spectrum; the first theoretical neutron energy spectrum φ0(E g This can be understood as the theoretical neutron energy spectrum at the target location after the neutron source passes through M media under optimal operating conditions, where the parameters of the M media are all optimal values. The parameters of the media may include, but are not limited to, the density, size, and temperature of the media. The optimal values ​​of the parameters of the M media are preset values, specifically determined based on parameters such as the energy response of the detector and the detector's placement.

[0063] In the embodiments of this application, since the actual values ​​and optimal values ​​of parameters such as density, size, and temperature of each medium will deviate to some extent, this deviation may be caused by manufacturing processes or measurement conditions. Therefore, the neutron energy spectrum corresponding to multiple operating conditions can be obtained by combining the optimal values ​​of each parameter with the error of each parameter.

[0064] In this embodiment, the second theoretical neutron spectrum can be understood as including I theoretical neutron spectra of M media under I sets of perturbation conditions, where I is a positive integer. The parameter values ​​of the M parameters under the perturbation conditions are obtained by adding or subtracting error amounts from their optimal values. The second theoretical neutron spectrum can be expressed as φ i (E g ), i = 1, 2, ..., I, where I can be understood as the number of disturbance conditions, and I needs to be greater than or equal to the number of detectors N.

[0065] In one example, for the density parameter ρ1 of the first medium, the error is Δρ1. Therefore, the actual range of the density parameter of the first medium may cover from ρ1-Δρ1 to ρ1+Δρ1.

[0066] Step S400: Determine the expansion coefficients corresponding to each characteristic basis function based on the readings of each detector, the neutron energy spectrum response function corresponding to each detector, and the N characteristic basis functions.

[0067] In this embodiment, a pre-constructed table can be obtained containing the detector readings, the corresponding neutron energy spectrum response function, characteristic basis functions, and the expansion coefficients of each characteristic basis function. The expansion coefficients corresponding to each characteristic basis function can then be found based on the table.

[0068] In this embodiment, the relationship between the detector readings, the corresponding neutron spectrum response function, the characteristic basis functions, and the expansion coefficients of each characteristic basis function can be constructed. The relationship between the detector readings, the corresponding neutron spectrum response function, the characteristic basis functions, and the expansion coefficients of each characteristic basis function can be expressed as:

[0069]

[0070] Among them, C n R represents the reading of the nth detector. n (E g () represents the neutron energy spectrum response function corresponding to the nth detector. Let a represent the k-th characteristic basis function. k denoted by , where represents the expansion coefficient corresponding to the k-th characteristic basis function, N represents the number of detectors, and G represents the number of energy groups in the neutron energy spectrum response function; the values ​​of n range from 1 to N, the values ​​of k range from 1 to N, and the values ​​of g range from 1 to G.

[0071] In the embodiments of this application, after reading the readings of each detector, the expansion coefficients corresponding to each characteristic basis function can be solved according to the neutron energy spectrum response function, N characteristic basis functions and the relational formula.

[0072] Step S500: The sum of the products of each characteristic basis function and its corresponding expansion coefficient is determined as the target neutron energy spectrum at the target location under the action of the neutron source.

[0073] In this embodiment, after determining each characteristic basis function, the sum of the products of each characteristic basis function and its corresponding expansion coefficients can be determined as the target neutron energy spectrum at the target location under the influence of the neutron source. The target neutron energy spectrum can be expressed as:

[0074]

[0075] Wherein, φ(E) g ) represents the target neutron energy spectrum. Let a represent the characteristic basis function. k This represents the expansion coefficients corresponding to the characteristic basis functions. k = 1, 2, ..., N, meaning the number of characteristic basis functions equals the number of detectors.

[0076] Through steps S100-S500, the theoretical neutron energy spectrum of the neutron source at the target location after passing through M media is obtained; the neutron energy spectrum response functions corresponding to N detectors are obtained; N characteristic basis functions are extracted based on the theoretical neutron energy spectrum; the expansion coefficients corresponding to each characteristic basis function are determined according to the readings of each detector, the corresponding neutron energy spectrum response function of each detector, and the N characteristic basis functions; the sum of the products of each characteristic basis function and its corresponding expansion coefficient is determined as the target neutron energy spectrum at the target location under the influence of the neutron source. Thus, when extracting characteristic basis functions based on the theoretical neutron energy spectrum, the number of characteristic basis functions is made equal to the number of detectors, and a unique solution to the neutron energy spectrum can be obtained through solving, avoiding the underdetermined problem and improving the accuracy of the spectral solution.

[0077] In some implementations, obtaining the theoretical neutron energy spectrum at the target location after the neutron source has passed through M media includes:

[0078] Obtain the first theoretical neutron energy spectrum and the second theoretical neutron energy spectrum; the first theoretical neutron energy spectrum is the theoretical neutron energy spectrum at the target position after the neutron source passes through M media under optimal operating conditions, and the second theoretical neutron energy spectrum includes I theoretical neutron energy spectra at the target position after the neutron source passes through M media under I sets of perturbation operating conditions, where I is a positive integer.

[0079] Specifically, the theoretical neutron energy spectrum at the target location after the neutron source passes through M media can include a first theoretical neutron energy spectrum and a second theoretical neutron energy spectrum. The first theoretical neutron energy spectrum φ0(E g The first theoretical neutron energy spectrum can be understood as the theoretical neutron energy spectrum at the target location after the neutron source passes through M media under optimal conditions, where the parameters of the M media are all optimal values. The first theoretical neutron energy spectrum can be obtained through particle transport using the Monte Carlo method.

[0080] In this embodiment, the second theoretical neutron spectrum can be understood as including I theoretical neutron spectra at the target location after the neutron source passes through M media under I sets of perturbation conditions, where I is a positive integer. The perturbation conditions can be understood as parameter values ​​obtained by adding or subtracting error amounts from the optimal values ​​of the M parameters. The second theoretical neutron spectrum can be expressed as φ i (E g ), i = 1, 2, ..., I, where I can be understood as the number of disturbance conditions, and I needs to be greater than or equal to the number of detectors N.

[0081] In this embodiment, by obtaining the first theoretical neutron energy spectrum and the second theoretical neutron energy spectrum, both the theoretical neutron energy spectrum under optimal operating conditions and the theoretical neutron energy spectrum under the influence of parameter tolerances can be taken into account, thereby improving the accuracy of the target neutron energy spectrum determination.

[0082] In some implementations, obtaining the first theoretical neutron energy spectrum includes:

[0083] Obtain the optimal values ​​of each parameter for M media;

[0084] Based on the optimal value, the neutron energy spectrum of the first theory is determined.

[0085] Specifically, the first theoretical neutron energy spectrum φ0(E g The first theoretical neutron energy spectrum can be understood as the theoretical neutron energy spectrum at the target location after the neutron source passes through M media under optimal conditions. The parameters of the M media under optimal conditions are all at their optimal values. First, the optimal values ​​of each parameter in the M media are obtained, and then the first theoretical neutron energy spectrum is determined based on these optimal values. In one example, the Monte Carlo method can be used to obtain the first theoretical neutron energy spectrum through particle transport. The Monte Carlo method is a computational method based on random sampling and statistical simulation. Its core idea is to approximate the solution of mathematical problems or simulate complex phenomena through a large number of random experiments.

[0086] In this embodiment, by determining the first theoretical neutron energy spectrum, the theoretical neutron energy spectrum under optimal operating conditions can be taken into account, thereby improving the accuracy of subsequent calculations in determining the target neutron energy spectrum.

[0087] In some implementations, obtaining the second theoretical neutron energy spectrum includes:

[0088] Obtain the optimal values ​​and error values ​​of each parameter for M media;

[0089] For each parameter in M ​​media, the sum of the optimal value of the parameter and the error is determined as the upper limit of the parameter, and the difference between the optimal value of the parameter and the error of the parameter is determined as the lower limit of the parameter.

[0090] Determine I parameter combinations corresponding to M media; each parameter combination includes the target value of each parameter in the M media; the target value of each parameter is any value between the upper limit and the lower limit of the parameter; at least one parameter in each parameter combination has a different target value;

[0091] Based on I combinations of parameters, I second theoretical neutron energy spectra are determined.

[0092] Specifically, the second theoretical neutron spectrum can be understood as the I theoretical neutron spectra at the target location after the neutron source passes through M media under I perturbation conditions, where I is a positive integer. The perturbation conditions can be understood as the parameter values ​​obtained by adding or subtracting error values ​​from the optimal values ​​of the M parameters. First, the optimal values ​​and error values ​​of each parameter in the M media are obtained. For each parameter in the M media, the sum of the optimal value and the error value is determined as the upper limit of the parameter, and the difference between the optimal value and the error value is determined as the lower limit of the parameter.

[0093] In this embodiment, after determining the optimal, upper, and lower values ​​of each parameter, I parameter combinations corresponding to the M media are determined based on the optimal, upper, and lower values ​​of each parameter. Each of the I parameter combinations includes the target value of each parameter in the M media; the target value of each parameter is any value between the upper and lower values ​​of the parameter; and at least one parameter in each of the I parameter combinations has a different target value.

[0094] In the embodiments of this application, the target value of each parameter can be selected as the optimal value, upper limit value, or lower limit value of the parameter.

[0095] In one example, given the medium's parameters include density ρ, size L, and temperature T, each parameter has its own error values ​​Δρ, ΔL, and ΔT. For density ρ, these can be ρ+Δρ, ρ, or ρ-Δρ; for size L, L+ΔL, L, or L-ΔL; and for temperature T, T+ΔT, T, or T-ΔT. Perturbations can be performed sequentially or simultaneously, and the perturbation process must include the conditions for individual perturbations of all parameters. The perturbation amounts can be selected based on the deviations of each parameter from its nominal value. Combining these values ​​yields various perturbation calculations. A maximum of 27 combinations can be included, or any combination can be selected from these 27.

[0096] In one example, taking error quantities Δρ1, ΔL1, and ΔT1 as examples, there are a maximum of 27 combinations:

[0097] i=1: Density is ρ1+Δρ1, size is L1+ΔL1, temperature is T1+ΔT1;

[0098] i = 2: density is ρ1 + Δρ1, size is L1 + ΔL1, temperature is T1;

[0099] i=3: Density is ρ1+Δρ1, size is L1+ΔL1, temperature is T1-ΔT1;

[0100] i = 4: density is ρ1 + Δρ1, size is L1, temperature is T1 + ΔT1;

[0101] i = 5: Density is ρ1 + Δρ1, size is L1, temperature is T1;

[0102] i = 6: Density is ρ1 + Δρ1, size is L1, temperature is T1 - ΔT1;

[0103] …

[0104] i = I: density is ρ1-Δρ1, size is L1-ΔL1, temperature is T1-ΔT1;

[0105] At this time, I = 27.

[0106] In another example, some combinations can be selected from the 27 methods mentioned above, for example:

[0107] i = 1: Density is ρ1, size is L1, temperature is T1;

[0108] i = 2: Density is ρ1 + Δρ1, size is L1, temperature is T1;

[0109] i = 3: Density is ρ1 - Δρ1, size is L1, temperature is T1;

[0110] i = 4: density is ρ1, size is L1 + ΔL1, temperature is T1;

[0111] i = 5: Density is ρ1, size is L1-ΔL1, temperature is T1;

[0112] i = 6: Density is ρ1, size is L1, temperature is T1-ΔT1;

[0113] i = 7: Density is ρ1, size is L1, temperature is T1 + ΔT1;

[0114] At this point, I = 7. When making the selection, it is necessary to ensure that these state points cover a large area.

[0115] In this embodiment, by considering the possible error amounts of each parameter, the second theoretical neutron energy spectrum under multiple perturbation conditions is determined, which can improve the accuracy of subsequent calculations of the target neutron energy spectrum.

[0116] In some implementations, N characteristic basis functions are extracted based on the theoretical neutron energy spectrum, including:

[0117] Construct the matrix of the theoretical energy spectrum based on the theoretical neutron energy spectrum;

[0118] The matrix is ​​decomposed to obtain N characteristic basis functions.

[0119] Specifically, after obtaining the theoretical neutron energy spectrum, the matrix φ of the theoretical neutron energy spectrum can be constructed based on the theoretical neutron energy spectrum. G×(I+1) The matrix is ​​then decomposed to obtain N eigenvalue basis functions.

[0120] In one example, constructing the theoretical energy spectrum matrix involves arranging the first theoretical neutron energy spectrum and the second theoretical neutron energy spectrum into a matrix form, which can be specifically represented as:

[0121]

[0122] In this embodiment, after obtaining the matrix of the theoretical energy spectrum, the matrix can be decomposed. Eigenorthogonal decomposition can be used for decomposition. Eigenorthogonal decomposition is the process of decomposing a matrix into eigenvectors. Eigenvectors are the characteristic basis functions in this embodiment. For each energy spectrum, it can be obtained by multiplying and adding the characteristic basis functions and their corresponding expansion coefficients.

[0123] In this embodiment, by decomposing the matrix, the complex moments can be decomposed into a set of independent basis vectors and corresponding coefficients, making the calculation of the target neutron energy spectrum simpler.

[0124] In some implementations, the expansion coefficients corresponding to each characteristic basis function are determined based on the readings of each detector, the neutron energy spectrum response function corresponding to each detector, and N characteristic basis functions, including:

[0125] By substituting the readings of each detector, the corresponding neutron energy spectrum response function of each detector, and the N characteristic basis functions into the target formula, the expansion coefficients corresponding to each characteristic basis function are obtained.

[0126] The objective formula is:

[0127]

[0128] Among them, C n R represents the reading of the nth detector. n (E g () represents the neutron energy spectrum response function corresponding to the nth detector. Let a represent the k-th characteristic basis function. kdenoted by , where represents the expansion coefficient corresponding to the k-th characteristic basis function, N represents the number of detectors, and G represents the number of energy groups in the neutron energy spectrum response function; n ranges from 1 to N, and k ranges from 1 to N.

[0129] Specifically, after determining the readings of each detector, the corresponding neutron energy spectrum response function of each detector, and N characteristic basis functions, the above parameters can be substituted into the target formula to obtain the expansion coefficients corresponding to each characteristic basis function.

[0130] In this embodiment of the application, the target formula can be:

[0131] Among them, C n This represents the reading of the nth detector, which can be obtained directly. R n (E g () represents the neutron energy spectrum response function corresponding to the nth detector. Let a represent the k-th characteristic basis function. k Let represent the expansion coefficients corresponding to the k-th characteristic basis function, N represent the number of detectors, and G represent the number of energy groups in the neutron spectrum response function; n ranges from 1 to N, and k ranges from 1 to N. Even if the number of characteristic basis functions is equal to the number of detectors, a unique solution can be obtained.

[0132] In one instance, with three detectors included, three target formulas can be constructed:

[0133]

[0134] Solving the linear system of equations consisting of the three objective formulas will determine the expansion coefficients corresponding to each characteristic basis function.

[0135] In this embodiment, the accuracy of the expansion coefficients can be improved by constructing the relationship between the readings of each detector, the neutron energy spectrum response function corresponding to each detector, and the N characteristic basis functions.

[0136] Please see Figure 3 This is a second schematic flowchart of the neutron energy spectrum interpretation method provided in the embodiments of this application. Figure 3 As shown, this spectral interpretation method includes the following steps:

[0137] Step S301: Obtain the best-estimated theoretical neutron energy spectrum based on the analysis object.

[0138] Step S302: Based on the analysis object, a series of theoretical neutron energy spectra are obtained by perturbation.

[0139] Step S303: Extract characteristic basis functions from the theoretical neutron energy spectrum.

[0140] Step S304: Use detector readings to determine the expansion coefficients of the optimal estimated neutron energy spectrum with respect to the characteristic basis functions.

[0141] Step S305: Obtain the final neutron energy spectrum.

[0142] In the embodiments of this application, the object of analysis refers to a device capable of providing a neutron energy spectrum. This device is composed of various materials arranged together, and the optimal input parameters are the nominal density, nominal size, etc. of these materials and their arrangement.

[0143] In the embodiments of this application, the specific implementation can be found in the foregoing description, and will not be repeated here.

[0144] Please see Figure 4 This is a schematic diagram of the neutron energy spectrum interpretation device provided in an embodiment of this application. The neutron energy spectrum interpretation device is applied to a spectrum interpretation equipment, which includes N detectors, each detector used to measure the neutron energy spectrum at the target position after the neutron source has passed through M media; N and M are both positive integers. A second aspect of this application provides a neutron energy spectrum interpretation device 40, which includes:

[0145] The first acquisition module 41 is used to acquire the theoretical neutron energy spectrum of the neutron source at the target position after passing through M media;

[0146] The second acquisition module 42 is used to acquire the neutron energy spectrum response functions corresponding to the N detectors respectively;

[0147] Extraction module 43 is used to extract N characteristic basis functions based on the theoretical neutron energy spectrum;

[0148] The first determining module 44 is used to determine the expansion coefficients corresponding to each characteristic basis function based on the readings of each detector, the neutron energy spectrum response function corresponding to each detector, and N characteristic basis functions.

[0149] The second determining module 45 is used to determine the sum of the products of each characteristic basis function and its corresponding expansion coefficient as the target neutron energy spectrum at the target location under the action of the neutron source.

[0150] The neutron energy spectrum descaling device 40 provided in the second aspect of the embodiments of this application can realize the various processes implemented in the above method embodiments and achieve the same beneficial effects. To avoid repetition, it will not be described again here.

[0151] Please see Figure 5This is a schematic diagram of the structure of the spectrum interpretation device provided in the embodiment of this application. The embodiment of this application also provides a spectrum interpretation device 5000, including a processor 5100 and a memory 5200. The memory 5200 stores machine-executable instructions that can be executed by the processor 5100. The processor 5100 can execute the machine-executable instructions to implement the above-mentioned neutron energy spectrum interpretation method.

[0152] In some embodiments, this application also provides a machine-readable storage medium storing instructions that, when executed by a processor, cause the processor to implement the above-described neutron energy spectrum descaling method.

[0153] In some embodiments, this application also provides a computer program product, including a computer program that, when executed by a processor, implements the neutron energy spectrum interpretation method according to the above embodiments.

[0154] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0155] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 The computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0156] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0157] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0158] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0159] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0160] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

[0161] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method for interpreting neutron energy spectra, characterized in that, It is applied to a spectrum interpretation device, which includes N detectors, each of which is used to measure the neutron energy spectrum at the target position after the neutron source has passed through M media; Both N and M are positive integers; The spectral interpretation method includes: Obtain the theoretical neutron energy spectrum at the target location after the neutron source passes through the M media; Obtain the neutron energy spectrum response functions corresponding to the N detectors respectively; Based on the theoretical neutron energy spectrum, N characteristic basis functions are extracted; Based on the readings of each detector, the neutron energy spectrum response function corresponding to each detector, and the N characteristic basis functions, the expansion coefficients corresponding to each characteristic basis function are determined. The sum of the products of each characteristic basis function and its corresponding expansion coefficient is determined as the target neutron energy spectrum at the target location under the action of the neutron source; Obtaining the theoretical neutron energy spectrum at the target location after the neutron source has passed through the M media includes: Obtain the first theoretical neutron energy spectrum and the second theoretical neutron energy spectrum; the first theoretical neutron energy spectrum is the theoretical neutron energy spectrum of the neutron source at the target position after passing through the M media under the optimal operating conditions, and the second theoretical neutron energy spectrum includes the I theoretical neutron energy spectra of the neutron source at the target position after passing through the M media under I sets of perturbation conditions, where I is a positive integer; Obtaining the second-theory neutron energy spectrum includes: Obtain the optimal values ​​and error amounts of each parameter for the M media; For each parameter in the M media, the sum of the optimal value of the parameter and the error is determined as the upper limit of the parameter, and the difference between the optimal value of the parameter and the error of the parameter is determined as the lower limit of the parameter. I parameter combinations are determined for the M media; each parameter combination includes the target value of each parameter in the M media; the target value of each parameter is any value between the upper limit value and the lower limit value; at least one parameter in each parameter combination has a different target value; Based on the I parameter combinations, the I second theoretical neutron energy spectra are determined.

2. The spectral interpretation method according to claim 1, characterized in that, Obtaining the first-theory neutron energy spectrum includes: Obtain the optimal values ​​of each parameter of the M media; Based on the optimal value, the first theoretical neutron energy spectrum is determined.

3. The spectral interpretation method according to claim 1, characterized in that, The extraction of N characteristic basis functions based on the theoretical neutron energy spectrum includes: Construct the matrix of the theoretical energy spectrum based on the theoretical neutron energy spectrum; The matrix is ​​decomposed to obtain the N characteristic basis functions.

4. The spectral interpretation method according to claim 1, characterized in that, The step of determining the expansion coefficients corresponding to each characteristic basis function based on the readings of each detector, the neutron energy spectrum response function corresponding to each detector, and the N characteristic basis functions includes: The expansion coefficients corresponding to each characteristic basis function are obtained by substituting the readings of each detector, the neutron energy spectrum response function of each detector, and the N characteristic basis functions into the target formula. The target formula is as follows: （1） in, Indicates the first Readings from each detector Indicates the first Neutron energy spectrum response function corresponding to each detector Indicates the first Characteristic basis functions, Indicates the relationship with the first The expansion coefficients corresponding to the characteristic basis functions. Indicates the number of detectors. The energy group number represents the neutron energy spectrum response function; n ranges from 1 to N, and k ranges from 1 to N. The value of g ranges from 1 to G.

5. A neutron energy spectrum interpretation device, characterized in that, It is applied to a spectrum interpretation device, which includes N detectors, each of which is used to measure the neutron energy spectrum at the target position after the neutron source has passed through M media; Both N and M are positive integers; The spectrum interpretation device includes: The first acquisition module is used to acquire the theoretical neutron energy spectrum of the neutron source at the target position after passing through the M media; The second acquisition module is used to acquire the neutron energy spectrum response functions corresponding to the N detectors respectively; The extraction module is used to extract N characteristic basis functions based on the theoretical neutron energy spectrum; The first determining module is used to determine the expansion coefficients corresponding to each characteristic basis function based on the readings of each detector, the neutron energy spectrum response function corresponding to each detector, and the N characteristic basis functions. The second determining module is used to determine the sum of the products of each characteristic basis function and its corresponding expansion coefficient as the target neutron energy spectrum at the target location under the action of the neutron source; The first acquisition module is used for: Obtain the first theoretical neutron energy spectrum and the second theoretical neutron energy spectrum; the first theoretical neutron energy spectrum is the theoretical neutron energy spectrum of the neutron source at the target position after passing through the M media under the optimal operating conditions, and the second theoretical neutron energy spectrum includes the I theoretical neutron energy spectra of the neutron source at the target position after passing through the M media under I sets of perturbation conditions, where I is a positive integer; The first acquisition module is further configured to: Obtain the optimal values ​​and error amounts of each parameter for the M media; For each parameter in the M media, the sum of the optimal value of the parameter and the error is determined as the upper limit of the parameter, and the difference between the optimal value of the parameter and the error of the parameter is determined as the lower limit of the parameter. I parameter combinations are determined for the M media; each parameter combination includes the target value of each parameter in the M media; the target value of each parameter is any value between the upper limit value and the lower limit value; at least one parameter in each parameter combination has a different target value; Based on the I parameter combinations, the I second theoretical neutron energy spectra are determined.

6. A spectrum interpretation device, characterized in that, include: The memory is configured to store instructions; And a processor configured to retrieve the instructions from the memory and, when executing the instructions, to implement the neutron energy spectrum despectral method according to any one of claims 1 to 4.

7. A machine-readable storage medium, characterized in that, The machine-readable storage medium stores instructions for causing the machine to perform a neutron energy spectrum decomposition method according to any one of claims 1 to 4.

8. A computer program product, characterized in that, When the instructions in the computer program product are executed by the processor of the spectrum descaling device, the spectrum descaling device performs the neutron energy spectrum descaling method as described in any one of claims 1 to 4.

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