Material cross-section library construction method, dose assessment method, and system

Abstract

A material cross-section library construction method, a dose assessment method, and a system. The material cross-section library construction method comprises: setting a material energy node; acquiring material information, the material information at least comprising constituent nuclides and nuclide particle number density; and constructing a material cross-section library on the basis of the material energy node and the material information. The dose assessment method further comprises: performing particle simulation calculation on the basis of the material cross-section library to obtain a cross-section value of a material where particles are located; and assessing a dose on the basis of the cross-section value of the material where the particles are located.

Description

Method for constructing material cross-section library, dose evaluation method and system TECHNICAL FIELD

[0001] The present application relates to the technical field of computers, and particularly relates to a method for constructing a material cross-section library, a dose evaluation method and a system. BACKGROUND

[0002] With the development of atomic science, radiotherapy such as cobalt-60, linear accelerator, electron beam, etc. has become one of the main means of cancer treatment. However, traditional photon or electron therapy is limited by the physical conditions of the radiation itself, and while killing tumor cells, it also causes damage to a large number of normal tissues along the beam path; in addition, due to the different sensitivities of tumor cells to radiation, the treatment effect of traditional radiotherapy on malignant tumors with high radiation resistance (such as glioblastoma multiforme and melanoma) is often poor.

[0003] In order to reduce the radiation damage to normal tissues around the tumor, the concept of targeted therapy in chemotherapy is applied to radiotherapy; and for tumor cells with high radiation resistance, radiation sources with high relative biological effectiveness (RBE) are actively developed, such as proton therapy, heavy particle therapy, and neutron capture therapy. Among them, neutron capture therapy is a combination of the above two concepts, such as boron neutron capture therapy (BNCT), which provides a better choice for cancer treatment than traditional radiotherapy by using boron-containing drugs to specifically accumulate in tumor cells and precise beam control.

[0004] Boron neutron capture therapy is a method that uses boron (10B) containing drugs to have a high capture cross section of thermal neutrons, generates two heavy charged particles of 4He and 7Li through 10B(n, α)7Li neutron capture and nuclear fission reaction, and the total range of the two particles is equivalent to the size of a cell, so the radiation damage to the organism can be limited to the cellular level. When boron-containing drugs selectively accumulate in tumor cells, combined with an appropriate neutron source, the purpose of locally killing tumor cells without causing too much damage to normal tissues can be achieved.

[0005] In boron neutron capture therapy, dose evaluation is often needed to develop a treatment plan, and the most accurate and reliable method for dose evaluation is the Monte Carlo method. SUMMARY

[0006] When the Monte Carlo method is used for dose evaluation, cross section values of all nuclei of a material in which a particle is located are accumulated to obtain a cross section value of the material in which the particle is located. The above process is usually performed by a processor, and the calculation is inefficient due to a large amount of calculation and a large number of calculation branches.

[0007] In view of the above technical problems, the present application provides a material cross section library construction method, a dose evaluation method and a system, which can effectively improve the calculation efficiency.

[0008] In a first aspect, the present application provides a material cross section library construction method. The method comprises:

[0009] Setting a material energy node;

[0010] Obtaining material information; the material information at least comprises: constituent nuclei and nuclear particle number density;

[0011] Constructing a material cross section library according to the material energy node and the material information.

[0012] In one of the embodiments, the setting of the material energy node comprises:

[0013] Determining a minimum nuclear energy node value and a maximum nuclear energy node value based on the nuclear cross section library of the constituent nuclei, and determining the minimum nuclear energy node value as the minimum material energy node and the maximum nuclear energy node value as the maximum material energy node;

[0014] Setting the material energy node according to the minimum material energy node and the maximum material energy node.

[0015] In one of the embodiments, the setting of the material energy node according to the minimum material energy node and the maximum material energy node comprises:

[0016] Uniformly logarithmically interpolating a preset number of energy intervals between the minimum material energy node and the maximum material energy node to obtain the material energy node.

[0017] In one of the embodiments, the setting of the material energy node according to the minimum material energy node and the maximum material energy node comprises:

[0018] Uniformly logarithmically interpolating a preset number of energy intervals between the minimum material energy node and the maximum material energy node to obtain the uniformly logarithmically interpolated energy node;

[0019] Determining resonance energy nodes of the constituent nuclei based on the nuclear cross section library of the constituent nuclei;

[0020] Adding the resonance energy nodes of the constituent nuclei to the uniformly logarithmically interpolated energy node to obtain the material energy node.

[0021] In one of the embodiments, based on the nuclide cross section library of the constituent nuclide, the resonance energy node of the constituent nuclide is determined, comprising:

[0022] Based on the nuclide cross section library of the constituent nuclide, the nuclide cross section value of the constituent nuclide at a plurality of continuous nuclide energy nodes is obtained;

[0023] According to the nuclide cross section value of the constituent nuclide at a plurality of continuous nuclide energy nodes, whether the constituent nuclide has a wave peak or a wave trough is identified;

[0024] When it is identified that the constituent nuclide has a wave peak or a wave trough, the corresponding plurality of continuous nuclide energy nodes are determined as the resonance energy node of the constituent nuclide.

[0025] In one of the embodiments, the material cross section library is constructed according to the material energy node and the material information, comprising:

[0026] According to the nuclide cross section library of the constituent nuclide, the nuclide cross section value of the constituent nuclide corresponding to the material energy node is determined;

[0027] According to the nuclide cross section value of the constituent nuclide corresponding to the material energy node and the nuclide particle number density, the material cross section value of the material energy node is determined;

[0028] Based on the material energy node and the material cross section value, the material cross section library is constructed.

[0029] In one of the embodiments, according to the nuclide cross section library of the constituent nuclide, the nuclide cross section value of the constituent nuclide corresponding to the material energy node is determined, comprising:

[0030] Whether the material energy node is a nuclide energy node of the nuclide cross section library of the constituent nuclide is identified;

[0031] If the material energy node is a nuclide energy node of the nuclide cross section library of the constituent nuclide, the nuclide cross section value corresponding to the nuclide energy node is obtained as the nuclide cross section value of the constituent nuclide corresponding to the material energy node;

[0032] If the material energy node is not a nuclide energy node of the nuclide cross section library of the constituent nuclide, the first nuclide energy node and the second nuclide energy node adjacent to the material energy node in the nuclide cross section library are obtained, wherein the first nuclide energy node is smaller than the second nuclide energy node, the first nuclide cross section value corresponding to the first nuclide energy node and the second nuclide cross section value corresponding to the second nuclide energy node are obtained, and the nuclide cross section value of the constituent nuclide corresponding to the material energy node is determined according to the material energy node, the first nuclide energy node, the second nuclide energy node, the first nuclide cross section value and the second nuclide cross section value.

[0033] In one of the embodiments, the method for determining the cross section value of the constituent nuclide corresponding to the material energy node according to the material energy node, the first nuclide energy node, the second nuclide energy node, the first nuclide cross section value and the second nuclide cross section value comprises:

[0034] The method for determining the cross section value of the constituent nuclide corresponding to the material energy node according to the material energy node, the first nuclide energy node and the second nuclide energy node comprises:

[0035] In a second aspect, the application further provides a dose evaluation method. The method comprises:

[0036] Setting a material energy node;

[0037] Obtaining material information of the three-dimensional voxel model; the material information at least comprises: constituent nuclides and nuclide particle number density;

[0038] Constructing a material cross section library according to the material energy node and the material information;

[0039] Performing particle simulation calculation according to the material cross section library to obtain the cross section value of the material where the particle is located; and evaluating the dose according to the cross section value of the material where the particle is located.

[0040] In one of the embodiments, the method for obtaining the cross section value of the material where the particle is located according to the material cross section library comprises:

[0041] Determining the first material energy node and the second material energy node adjacent to the particle energy based on the material energy node; the first material energy node is less than the particle energy, and the second material energy node is greater than the particle energy;

[0042] Obtaining the first material cross section value corresponding to the first material energy node and the second material cross section value corresponding to the second material energy node in the material cross section library corresponding to the material where the particle is located;

[0043] Obtaining the cross section value of the material where the particle is located according to the particle energy, the first material energy node, the second material energy node, the first material cross section value and the second material cross section value.

[0044] In one of the embodiments, the method for obtaining the cross section value of the material where the particle is located according to the particle energy, the first material energy node, the second material energy node, the first material cross section value and the second material cross section value comprises:

[0045] The method for obtaining the cross section value of the material where the particle is located according to the particle energy, the first material energy node and the second material energy node comprises:

[0046] Thirdly, this application also provides a dose assessment system. The system includes:

[0047] The Material Section Library Construction Module is used to build a material section library for 3D voxel models.

[0048] The particle simulation calculation module is used to perform particle simulation calculations based on the material section library to obtain the cross-sectional value of the material in which the particle is located.

[0049] The dose assessment module is used to assess the dose based on the cross-sectional value of the material in which the particle is located;

[0050] The material section library construction module includes:

[0051] Material energy node setting unit, used to set material energy nodes;

[0052] The material information acquisition unit is used to acquire the material information of the three-dimensional voxel model; the material information includes at least: the constituent nuclides and the number density of nuclide particles.

[0053] The material section library construction unit is used to construct a material section library based on material energy nodes and material information.

[0054] In one embodiment, the material energy node setting unit includes:

[0055] The first energy node setting sub-unit is used to determine the minimum and maximum nuclide energy node values ​​based on the nuclide cross-section library of the constituent nuclides. The minimum nuclide energy node value is determined as the minimum material energy node, and the maximum nuclide energy node value is determined as the maximum material energy node.

[0056] The second energy node setting sub-unit is used to set the material energy node based on the minimum material energy node and the maximum material energy node.

[0057] In one embodiment, the second energy node is configured with a subunit, including:

[0058] The uniform logarithmic interpolation unit is used to uniformly logarithmically interpolate a preset number of energy intervals between the minimum material energy node and the maximum material energy node to obtain the energy node after uniform logarithmic interpolation.

[0059] The resonance node determination unit is used to determine the resonance energy nodes of the constituent nuclides based on the nuclide cross-section library of the constituent nuclides.

[0060] The resonant node addition unit is used to add the resonant energy nodes of the constituent nuclides to the energy nodes after uniform logarithmic interpolation, thereby obtaining the material energy nodes.

[0061] In one embodiment, the material section library building unit includes:

[0062] The nuclide cross-section value determination sub-unit is used to determine the nuclide cross-section value of the constituent nuclide corresponding to the material energy node based on the nuclide cross-section library of the constituent nuclides.

[0063] The material cross-section value determination sub-unit is used to determine the material cross-section value of the material energy node based on the nuclide cross-section value and the nuclide particle number density corresponding to the material energy node.

[0064] The material section library construction sub-unit is used to construct the material section library based on material energy nodes and material section values.

[0065] In one embodiment, the nuclide cross-section value determining sub-unit includes:

[0066] The nuclide energy node identification unit is used to identify whether a material energy node is a nuclide energy node of the nuclide cross-section library that makes up the nuclide.

[0067] The first nuclide cross-section value acquisition unit is used to acquire the nuclide cross-section value corresponding to the nuclide energy node as the nuclide cross-section value corresponding to the material energy node if the material energy node is a nuclide energy node in the nuclide cross-section library of the constituent nuclide.

[0068] The second nuclide cross-section value acquisition unit is used to acquire, if the material energy node is not a nuclide energy node in the nuclide cross-section library that is adjacent to the material energy node, wherein the first nuclide energy node is smaller than the second nuclide energy node, and to acquire the first nuclide cross-section value corresponding to the first nuclide energy node and the second nuclide cross-section value corresponding to the second nuclide energy node. The unit determines the nuclide cross-section value of the constituent nuclide corresponding to the material energy node based on the material energy node, the first nuclide energy node, the second nuclide energy node, the first nuclide cross-section value and the second nuclide cross-section value.

[0069] In one embodiment, the particle simulation calculation module includes:

[0070] The adjacent energy node determination unit is used to determine the first material energy node and the second material energy node adjacent to the particle energy based on the material energy node; the first material energy node is less than the particle energy, and the second material energy node is greater than the particle energy;

[0071] The material cross-section value acquisition unit is used to acquire the first material cross-section value corresponding to the first material energy node and the second material cross-section value corresponding to the second material energy node from the material cross-section library corresponding to the material where the particle is located;

[0072] The particle simulation calculation unit is used to obtain the cross-sectional value of the material where the particle is located based on the particle energy, the first material energy node, the second material energy node, the first material cross-sectional value, and the second material cross-sectional value.

[0073] The aforementioned method for constructing the material cross-section library, the dose assessment method, and the system construct the material cross-section library based on the material energy node, constituent nuclides, and nuclide particle number density. This allows the conversion of the nuclide cross-section library into a material cross-section library, thereby improving computational efficiency during dose assessment. Specifically, when using a GPU for dose assessment, the GPU can directly calculate the cross-section value of the material containing the particle based on the material cross-section library, without needing to calculate the cross-section value of each constituent nuclide within the material. This reduces the logical computation branches of the GPU, significantly lowering the GPU's material cross-section value calculation time and improving its computational efficiency. Furthermore, when using a CPU for dose assessment, the computational load on the CPU for material cross-section values ​​can be reduced, thereby improving the CPU's computational efficiency. Attached Figure Description

[0074] Figure 1 is a flowchart illustrating a method for constructing a material section library in one embodiment;

[0075] Figure 2 is a schematic diagram of the process of setting up a material energy node in one embodiment;

[0076] Figure 3 is a schematic diagram of the cross-sectional changes of common nuclides in boron neutron capture therapy as a function of energy in one embodiment;

[0077] Figure 4 is a schematic diagram of a partial resonance peak region of the O16 nuclide in one embodiment;

[0078] Figure 5 is a flowchart illustrating the dose assessment method in one embodiment;

[0079] Figure 6 is a schematic diagram of a process for obtaining the cross-sectional value of the material where the particle is located by performing particle simulation calculations based on a material cross-section library in one embodiment.

[0080] Figure 7 is a block diagram of a dose assessment system in one embodiment;

[0081] Figure 8 is an internal structure diagram of a computer device in one embodiment. Detailed Implementation

[0082] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0083] Radiation therapy is a crucial method in cancer treatment. To maximize the killing of cancer cells while minimizing damage to normal cells, CT or PET scans are typically performed before treatment. The scans provide information on the target's tissue material and boron concentration distribution. A three-dimensional voxel model is then created based on this information. The transport process of radiation particles is simulated using this model to assess the dose distribution, and the optimal dose distribution scheme is selected as the treatment plan. Dose assessment is a core component of radiotherapy planning, and the most accurate and reliable method for dose assessment is currently the Monte Carlo method. The Monte Carlo method can simulate the transport trajectory of each particle, thus accurately assessing the dose distribution within the target. This dose assessment process is usually executed by a processor, primarily a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). During dose assessment, the cross-sectional values ​​of all nuclides within the material containing the particle are summed to obtain the cross-sectional value of the material containing the particle. Different particles reside in different materials, resulting in variations in the composition and number of nuclides. The material in which the particle is located refers to the material of the human tissue in which the particle is located, that is, the material of the voxel mesh in which the particle is located in the three-dimensional voxel model. It is often obtained through the HU (Hounsfield Unit) value in CT images, but it can also be obtained through other medical image data known to those skilled in the art.

[0084] However, while CPU computation employs parallel processing, its high computational load results in low efficiency. Similarly, GPU computation for calculating the cross-sectional values ​​of the material containing the particle is inefficient due to the numerous computational branches. Therefore, to address these technical issues, a method for constructing a material cross-section library is provided.

[0085] In the embodiment shown in Figure 1, a method for constructing a material cross-section library is provided. Taking the application of this method to a dose assessment system as an example, the method includes the following steps:

[0086] Step 102: Set the material energy node.

[0087] In this context, a material energy node refers to an energy node that is reconfigured during the conversion of a nuclide cross-section library into a material cross-section library. This node is used to directly calculate the material cross-section value of the material containing the particle. For example, a material energy node may include 10... 1 eV, 10 2 eV, 10 3 eV, 10 4 eV and 10 5eV, of course, those skilled in the art can also set it to other reasonable energy nodes.

[0088] Step 104: Obtain material information; the material information includes at least the constituent nuclides and the number density of nuclide particles.

[0089] For example, Table 1 below shows the constituent nuclides and nuclide number densities corresponding to some human tissue materials, which is the material information. Human tissue materials include air, lungs, adipose tissue, muscle, and bone. Among them, air refers to the air present in the human body. Due to the differences in density and the different nuclide compositions of bones with different densities, bones of different densities are classified into different human tissue materials according to their HU values, such as bone1, bone2, etc., as shown in Table 1. Different human tissue materials may have the same or different constituent nuclides, and even if the human tissue materials are the same, the corresponding nuclide number densities may be different. As shown in the table below, the constituent nuclides of air are N, O, and Ar, with N having a particle number density of 75.5%, O 23.2%, and Ar 1.3%. The constituent nuclides of lungs are H, C, N, O, Na, P, S, Cl, and K, with H having a particle number density of 10.3%, C 10.5%, N 3.1%, O 74.9%, Na 0.2%, P 0.2%, S 0.3%, Cl 0.3%, and K 0.2%. Besides the human tissue materials shown in Table 1, information on other human tissue materials can be directly obtained from publicly available information by those skilled in the art, and will not be elaborated upon here.

[0090] Table 1. Compositional nuclides (weight percentage of elements) for materials from different human tissues

[0091] Step 106: Construct a material cross-section library based on material energy nodes and material information.

[0092] Specifically, material information is acquired, including at least the constituent nuclides and the nuclide number density of each constituent nuclide. Based on the nuclide cross-section library and the nuclide number density, the material cross-section values ​​of pre-set material energy nodes are determined, and a material cross-section library is constructed based on the material cross-section values ​​of the material energy nodes.

[0093] Based on the constituent nuclides of the material, a nuclide cross-section library is obtained for each constituent nuclide. Each nuclide corresponds to a separate cross-section library, which includes the cross-section values ​​of that nuclide at multiple nuclide energy nodes. The magnitude of the cross-section value corresponding to each nuclide energy node represents the ease with which that nuclide undergoes a nuclear reaction with a neutron at the corresponding energy level. This value is related not only to the nuclide type but also to the neutron energy, and is a function of the neutron energy. The material energy nodes are then set according to the nuclide cross-section library of the material's constituent nuclides, thus obtaining the material energy nodes for that material.

[0094] In this embodiment, a material cross-section library is constructed based on the material energy node, constituent nuclides, and nuclide particle number density. This allows the nuclide cross-section library to be converted into a material cross-section library, thereby improving computational efficiency during dose assessment. Specifically, when using a GPU for dose assessment, the GPU can directly calculate the cross-section value of the material containing the particle based on the material cross-section library, without needing to calculate the cross-section value of each constituent nuclide within the material. This reduces the logical computation branches of the GPU, significantly lowering the GPU's material cross-section value calculation time and improving its computational efficiency. When using a CPU for dose assessment, the CPU's material cross-section value calculation workload can be reduced, thereby improving its computational efficiency.

[0095] As shown in one embodiment of Figure 2, step 102, setting the material energy node, includes:

[0096] Step 202: Based on the nuclide cross-section library of the constituent nuclides, determine the minimum and maximum nuclide energy node values ​​among all the nuclide energy nodes of the constituent nuclides. The minimum nuclide energy node value is determined as the minimum material energy node, and the maximum nuclide energy node value is determined as the maximum material energy node.

[0097] Taking air as an example, as shown in Table 1, the constituent nuclides of air are N, O and Ar. Based on the nuclide cross-section library of N, O and Ar, the minimum and maximum nuclide energy node values ​​among the three nuclides are determined. The minimum nuclide energy node value is determined as the minimum material energy node of air, and the maximum nuclide energy node value is determined as the maximum material energy node of air.

[0098] Step 204: Set the material energy nodes based on the minimum and maximum material energy nodes.

[0099] Multiple energy intervals are inserted between the minimum and maximum material energy nodes to obtain the material energy nodes. Specifically, the methods for setting material energy nodes can include Method 1 and Method 2. Method 1 refers to using uniform logarithmic interpolation, while Method 2 refers to setting them based on the cross-sectional variation patterns of the actual constituent nuclides.

[0100] In the above embodiments, since the energy nodes of the constituent nuclides of the material may be different, the minimum nuclide energy node value of all constituent nuclides of the material is determined as the minimum material energy node, and the maximum nuclide energy node value is determined as the maximum material energy node, thereby establishing the energy nodes of the material and realizing the conversion of the nuclide cross-section library into the material cross-section library.

[0101] In an optional embodiment of the above, when the material energy nodes are set using the first method, i.e., uniform logarithmic interpolation, step 204, setting the material energy nodes according to the minimum and maximum material energy nodes, includes: uniformly logarithmically interpolating a preset number of energy intervals between the minimum and maximum material energy nodes to obtain the material energy nodes.

[0102] The energy gap refers to the energy difference between adjacent material energy nodes.

[0103] Specifically, a preset number of energy intervals are uniformly logarithmically interpolated between the minimum and maximum material energy nodes, and the energy nodes corresponding to the energy intervals are taken as material energy nodes. For example, if M energy intervals are uniformly logarithmically interpolated, M+1 material energy nodes can be obtained.

[0104] The value of the i-th material energy node can be calculated using the following formula:

[0105] Among them, E i E represents the value of the i-th material energy node. max E represents the largest nuclide energy node. min This represents the smallest nuclide energy node.

[0106] Furthermore, the number of energy intervals for uniform logarithmic interpolation is related to the number of nuclide energy nodes in the nuclide cross-section library of all constituent nuclides of the material. One preferred approach is to use an energy interval number close to the maximum number of nuclide energy nodes in the constituent nuclides of the material to ensure the accuracy of the material cross-section library, thereby guaranteeing the calculation accuracy of the treatment plan dose assessment system based on the material cross-section library. For example, the constituent nuclides of air are O16, N14, and Ar40. In the nuclide cross-section library (ENDF / B7.1), there are 1826 nuclide energy nodes for N14, 2998 for O16, and 22747 for Ar40. To ensure the accuracy of the air material cross-section library, the number of air material energy nodes can be directly set to 22747. Alternatively, it can be set to a value greater than 22747 but close to it, such as 23000, to facilitate the calculation of material energy nodes while ensuring the accuracy of the material cross-section library. In another preferred embodiment, considering the lower proportion of Ar40 and its lower reaction cross-section with neutrons compared to N14 and O16, the number of material energy nodes M in the material cross-section library is set to 20,000, slightly lower than the maximum number of energy nodes for Ar40 nuclides. This ensures the accuracy of the material cross-section library while effectively improving computational efficiency. Those skilled in the art can determine the appropriate number of material energy nodes based on the constituent nuclides of different materials and by comprehensively considering the nuclear reactions between different constituent nuclides and neutrons; this will not be elaborated upon here.

[0107] In this embodiment, the material energy node can be quickly determined by uniformly logarithmically interpolating a preset number of energy intervals between the minimum and maximum material energy nodes.

[0108] The first method described above is effective for nuclides whose cross-sectional values ​​have a relatively smooth distribution with energy. For nuclides whose cross-sectional values ​​oscillate with energy, i.e., nuclides with resonance peaks, the selection of specific energy nodes needs to be considered. Figure 3 shows a schematic diagram of the cross-sectional values ​​of common nuclides used in boron neutron capture therapy as a function of energy. The horizontal axis represents the neutron energy of the nuclide, and the vertical axis represents the cross-sectional value of the nuclide. It can be seen that in the low-energy region, the cross-sectional value changes smoothly with energy, but in the high-energy region, some resonance peaks appear. Resonance peaks can include peaks or troughs. In the region of cross-sectional resonance peaks, the selection of material energy nodes has a significant impact on the calculation of cross-sectional values. Therefore, the second method can be adopted, which involves setting the material energy nodes for each material based on the cross-sectional variation law of the actual constituent nuclides.

[0109] In another optional embodiment described above, when using method two, i.e., setting the material energy nodes for each material based on the cross-sectional variation law of the actual constituent nuclides, step 204, setting the material energy nodes based on the minimum and maximum material energy nodes, includes: uniformly logarithmically interpolating a preset number of energy intervals between the minimum and maximum material energy nodes to obtain uniformly logarithmically interpolated energy nodes; determining the resonance energy nodes of the constituent nuclides based on the nuclide cross-section library; and adding the resonance energy nodes of the constituent nuclides to the uniformly logarithmically interpolated energy nodes to obtain the material energy nodes.

[0110] Specifically, when setting material energy nodes based on the cross-sectional variation patterns of actual constituent nuclides, it is first necessary to uniformly logarithmically interpolate a preset number of energy intervals between the minimum and maximum material energy nodes to obtain uniformly logarithmically interpolated energy nodes. Then, based on the nuclide cross-section library of constituent nuclides, the resonance energy nodes of the constituent nuclides are determined. Here, a resonance energy node refers to the nuclide energy node corresponding to the cross-sectional resonance peak. The values ​​of the resonance energy nodes of the constituent nuclides are compared with those of the uniformly logarithmically interpolated energy nodes, and the resonance energy nodes of the constituent nuclides are added to the uniformly logarithmically interpolated energy nodes according to their values ​​to obtain the material energy nodes.

[0111] At this point, the material energy nodes are no longer uniformly distributed. During dose assessment, material energy nodes can be located using binary search or hash indexing. This process is more complex than directly searching from uniformly distributed energy nodes, but it is still much simpler than calculating the cross-sectional value of each constituent nuclide. Since the cross-sectional resonance peak regions of all constituent nuclides are taken into account, the accuracy of the material cross-sectional values ​​can be ensured. Binary search or hash indexing are commonly used search methods by those skilled in the art and will not be elaborated upon here.

[0112] Furthermore, based on the nuclide cross-section library of the constituent nuclides, the resonance energy nodes of the constituent nuclides are determined, including: obtaining the nuclide cross-section values ​​of the constituent nuclides at multiple consecutive nuclide energy nodes based on the nuclide cross-section library of the constituent nuclides; identifying whether the constituent nuclides have peaks or troughs based on the nuclide cross-section values ​​of the constituent nuclides at multiple consecutive nuclide energy nodes; when the constituent nuclides are identified to have peaks or troughs, the corresponding multiple consecutive nuclide energy nodes are determined as the resonance energy nodes of the constituent nuclides.

[0113] Specifically, the nuclide cross-section values ​​of the constituent nuclides at multiple consecutive nuclide energy nodes are obtained from the nuclide cross-section library. For example, the nuclide cross-section values ​​of the constituent nuclides at multiple consecutive nuclide energy nodes could be the nuclide cross-section values ​​at three consecutive nuclide energy nodes. Based on the nuclide cross-section values ​​of the constituent nuclides at multiple consecutive nuclide energy nodes, it is identified whether the constituent nuclide exhibits peaks or troughs. Both peaks and troughs exhibit a process of first rising and then falling, or first falling and then rising. Specifically, for a constituent nuclide, the change in cross-section var is calculated based on the nuclide cross-section values ​​at multiple consecutive nuclide energy nodes according to the following formula:

[0114] var=(σ(E1)-σ(E2))(σ(E2)-σ(E3)) (2)

[0115] Where σ(E1), σ(E2), and σ(E3) represent the nuclide cross-section values ​​of three consecutive nuclide energy nodes E1, E2, and E3.

[0116] If var is less than 0, it proves that there is a peak or trough directly at these three consecutive nuclide energy nodes. These three consecutive nuclide energy nodes are identified as the resonance energy nodes of the constituent nuclides and added to the energy nodes after uniform logarithmic interpolation, thus allowing all fluctuation scenarios to be considered.

[0117] Furthermore, to better account for energy fluctuations, the nuclide energy nodes to the left of E1 and to the right of E3 can also be included, meaning that one fluctuation considers five nuclide energy nodes.

[0118] Figure 4 shows a schematic diagram of some resonance peak regions of the O16 nuclide. The O16 nuclide has two peaks in the energy range of 320 keV-560 keV and 860 keV-1.1 MeV, that is, there are two resonance peaks. All nuclide energy nodes in these two energy ranges of the O16 nuclide need to be added to the energy nodes after uniform logarithmic interpolation.

[0119] In this embodiment, since the selection of energy nodes has a significant impact on the calculation of cross-sectional values ​​in the cross-sectional resonance peak region, the accuracy of material energy nodes can be improved by considering the resonance energy nodes in the cross-sectional resonance peak region of nuclides, which in turn helps to improve the accuracy of the material cross-sectional library.

[0120] In an exemplary embodiment, step 106, constructing a material cross-section library based on material energy nodes and material information, includes: determining the nuclide cross-section value of the constituent nuclide corresponding to the material energy node based on the nuclide cross-section library of the constituent nuclide; determining the material cross-section value of the material energy node based on the nuclide cross-section value of the constituent nuclide corresponding to the material energy node and the nuclide particle number density; and constructing a material cross-section library based on the material energy node and the material cross-section value.

[0121] Specifically, in the nuclide cross-section library of the constituent nuclides of the material, the nuclide cross-section values ​​corresponding to the material energy nodes are determined. Based on the nuclide cross-section value corresponding to each material energy node and the nuclide particle number density of the material's constituent nuclides, the material cross-section value for each material energy node is determined. A material cross-section library is constructed based on all material energy nodes and the material cross-section values ​​for each material energy node.

[0122] In a preferred embodiment, the material cross-section value of each material energy node is determined using the following formula, based on the nuclide cross-section value of the constituent nuclide corresponding to each material energy node and the nuclide particle number density of the material's constituent nuclide:

[0123] Where, ∑ t (E) represents the material cross-sectional value, E represents the material energy node, and N i σ represents the nuclide number density of the i-th constituent nuclide in each material. i (E) represents the cross-sectional value of the i-th constituent nuclide corresponding to the material energy node.

[0124] In this embodiment, based on the nuclide cross-section value and nuclide particle number density corresponding to the material energy node, the nuclide cross-section library can be converted into a material cross-section library, which is beneficial to improving the calculation efficiency of material cross-section values ​​during dose calculation.

[0125] In one optional embodiment of the above, determining the nuclide cross-section value of the constituent nuclide corresponding to the material energy node based on the nuclide cross-section library of the constituent nuclide includes: identifying whether the material energy node is a nuclide energy node in the nuclide cross-section library of the constituent nuclide; if the material energy node is a nuclide energy node in the nuclide cross-section library of the constituent nuclide, then obtaining the nuclide cross-section value corresponding to the nuclide energy node as the nuclide cross-section value of the constituent nuclide corresponding to the material energy node; if the material energy node is not a nuclide energy node in the nuclide cross-section library of the constituent nuclide, then obtaining the first nuclide energy node and the second nuclide energy node adjacent to the material energy node in the nuclide cross-section library, wherein the first nuclide energy node is smaller than the second nuclide energy node, and obtaining the first nuclide cross-section value corresponding to the first nuclide energy node and the second nuclide cross-section value corresponding to the second nuclide energy node, and determining the nuclide cross-section value of the constituent nuclide corresponding to the material energy node based on the material energy node, the first nuclide energy node, the second nuclide energy node, the first nuclide cross-section value and the second nuclide cross-section value.

[0126] Specifically, the material energy node may not coincide with the nuclide energy nodes in the nuclide cross-section library of its constituent nuclides. Therefore, the cross-sectional value of the constituent nuclide corresponding to the material energy node cannot be directly obtained from the nuclide cross-section library. In determining the nuclide cross-sectional value of the constituent nuclide corresponding to the material energy node, it is possible to identify whether the material energy node is a nuclide energy node in the nuclide cross-section library. If the material energy node is a nuclide energy node in the nuclide cross-section library, the nuclide cross-sectional value corresponding to the nuclide energy node is obtained as the nuclide cross-sectional value of the constituent nuclide corresponding to the material energy node. If the material energy node is not a nuclide energy node in the nuclide cross-section library, the first and second nuclide energy nodes adjacent to the material energy node in the nuclide cross-section library must be obtained first, where the first nuclide energy node is smaller than the second nuclide energy node. The first nuclide cross-sectional value corresponding to the first nuclide energy node and the second nuclide cross-sectional value corresponding to the second nuclide energy node are then obtained from the nuclide cross-section library. Therefore, the nuclide cross-sectional values ​​of the constituent nuclides corresponding to the material energy nodes are determined based on the material energy nodes, the first nuclide energy nodes, the second nuclide energy nodes, the first nuclide cross-sectional values, and the second nuclide cross-sectional values.

[0127] Furthermore, determining the nuclide cross-sectional value of the constituent nuclide corresponding to the material energy node based on the material energy node, the first nuclide energy node, the second nuclide energy node, the first nuclide cross-sectional value, and the second nuclide cross-sectional value includes: performing linear interpolation on the first nuclide cross-sectional value and the second nuclide cross-sectional value based on the material energy node, the first nuclide energy node, and the second nuclide energy node to obtain the nuclide cross-sectional value of the constituent nuclide corresponding to the material energy node.

[0128] The formula for linear interpolation of the cross-sectional values ​​of the first and second nuclides is as follows:

[0129] Where E is the material energy node, E1 and E2 are the first and second nuclide energy nodes adjacent to E in the cross-sectional database of the i-th constituent nuclide, respectively, and σ i (E1) and σ i (E2) represents the first nuclide cross-section value corresponding to the first nuclide energy node and the second nuclide cross-section value corresponding to the second nuclide energy node, respectively.

[0130] By combining equations (3) and (4) above, the material cross-sectional value of the material energy node can be calculated, thereby forming a cross-sectional database for each material.

[0131] Optionally, when the material energy node is not a nuclide energy node in the nuclide cross-section library constituting the nuclide, the method for determining the nuclide cross-section value corresponding to the material energy node can be logarithmic interpolation or a quadratic function method, in addition to linear interpolation. Logarithmic interpolation can be divided into two cases: one is to perform logarithmic interpolation only on the first and second nuclide cross-section values; the other is to perform logarithmic interpolation on the first and second nuclide cross-section values, the material energy node, the first nuclide energy node, and the second nuclide energy node.

[0132] In this embodiment, if the material energy node is a nuclide energy node in the nuclide cross-section library that makes up the nuclide, then the nuclide cross-section value corresponding to the nuclide energy node is obtained as the nuclide cross-section value of the constituent nuclide corresponding to the material energy node. If the material energy node is not a nuclide energy node in the nuclide cross-section library that makes up the nuclide, then the nuclide cross-section value corresponding to the nuclide energy node adjacent to the material energy node is obtained, thereby obtaining the nuclide cross-section value corresponding to the material energy node. This allows for flexible calculation of the nuclide cross-section value corresponding to the material energy node.

[0133] The following uses air as an example to illustrate the construction process of the material cross-section library. A large portion of the voxel mesh in the 3D voxel model is air. The nuclide composition of air is O16, N14, and Ar40, with particle number densities of 23.2%, 75.5%, and 1.3%, respectively. In the nuclide cross-section library (ENDF / B7.1), there are 1826 nuclide energy nodes for N14, 2998 for O16, and 22747 for Ar40. Considering the relatively low proportion of Ar40 and its lower reaction cross-section with neutrons compared to N14 and O16, the number of material energy nodes M in the air material cross-section library is set to 20000, slightly lower than the maximum number of Ar40 nuclide energy nodes. The minimum nuclide energy nodes for the three constituent nuclides of air are all 1E-5 eV; therefore, the minimum material energy node E in the air material cross-section library is... minThe maximum nuclide energy nodes for the three constituent nuclides of air are 1E-5 eV. Considering that the neutron energy in BNCT cannot exceed 2E7 eV, the maximum material energy node for the air material cross-section library is E... max Take 2E7eV. In E max and E min M material energy nodes are uniformly inserted in a logarithmic manner, where the 0th material energy node is E. min The Mth material energy node is E max The energy of the i-th material energy node can be obtained by referring to the above formula (1). After calculating the energy nodes of all material energy nodes of air based on the above formula (1), the material cross-section value of each material energy node of air is calculated based on the above formula (3). Finally, the material cross-section library of air is constructed based on all material energy nodes of air calculated by the above formula (1) and the material cross-section value of each material energy node of air calculated by the above formula (3).

[0134] The neutrons used in BNCT are thermal and ultrathermal neutrons, with energies ranging from 1E-5 eV to 1E4 eV. The material energy nodes in the material cross-section library have 14,633 energy nodes within this energy range, while Ar40, the nuclide with the most energy nodes, has only 1,847 energy nodes in this range (other nuclides have energy nodes higher than 1E4 eV). Within the energy range primarily considered by BCNT, the number of material energy nodes far exceeds the number of nuclide energy nodes, thus preventing any loss of accuracy during the conversion process.

[0135] In an exemplary embodiment, as shown in FIG5, a dose assessment method is provided. Taking the application of this method to a dose assessment system as an example, the method includes the following steps:

[0136] Step 502: Set the material energy node.

[0137] Step 504: Obtain material information for the three-dimensional voxel model; the material information includes at least the constituent nuclides and the number density of nuclide particles.

[0138] Step 506: Construct a material cross-section library based on material energy nodes and material information.

[0139] Step 508: Perform particle simulation calculations based on the material cross-section library to obtain the cross-sectional value of the material where the particle is located; evaluate the dose based on the cross-sectional value of the material where the particle is located.

[0140] Specifically, in step 502, in some optional implementations, different material energy nodes can be set for different materials in the three-dimensional voxel model, that is, material energy nodes are set based on the nuclide composition of each material. The specific material energy node setting method is the same as the aforementioned material energy node setting method, and will not be repeated here.

[0141] In some alternative implementations, all materials in the 3D voxel model can be assigned the same material energy nodes, that is, the material energy nodes are set based on the nuclide composition of all materials in the 3D voxel model. For example, in the 3D voxel model, there are two tissue materials: air and lung. According to Table 1, the constituent nuclides of air are N, O, and Ar, and the constituent nuclides of lung are H, C, N, O, Na, P, S, Cl, and K. In this implementation, air and lung can be assigned the same material energy nodes. Specifically, based on the nuclide cross-section library of all constituent nuclides of air and lung, namely N, O, Ar, H, C, Na, P, S, Cl, and K, the minimum and maximum nuclide energy node values ​​among all nuclides are identified. The minimum nuclide energy node value is determined as the minimum material energy node, and the maximum nuclide energy node value is determined as the maximum material energy node. Then, all material energy nodes are set according to the above material energy node setting method as the material energy nodes for air and lung tissue materials.

[0142] Specifically, in step 504, obtaining the material information of the three-dimensional voxel model can be one material or multiple materials, depending on the needs of dose assessment.

[0143] Optionally, the construction process of the material cross-section library in the dose assessment method is the same as the aforementioned method for constructing the material cross-section library, and will not be repeated here. Preferably, each material corresponds to one material cross-section library.

[0144] After constructing the material cross-section library, particle simulation calculations are performed based on the library to obtain the cross-sectional values ​​of the material in which the particle resides. Particle simulation refers to simulating the entire transport process of a particle from a radiation source model to a three-dimensional voxel model, and then assessing the dose based on the cross-sectional values ​​of the material in which the particle resides. The dose assessment method based on the cross-sectional values ​​of the material in which the particle resides can employ dose assessment methods familiar to those skilled in the art.

[0145] Further, as shown in Figure 6, step 508 involves performing particle simulation calculations based on the material cross-section library to obtain the cross-sectional values ​​of the material where the particle is located, including:

[0146] Step 602: Based on the material energy nodes, determine the first material energy node and the second material energy node adjacent to the particle energy; the first material energy node is less than the particle energy, and the second material energy node is greater than the particle energy.

[0147] Step 604: In the material cross-section library corresponding to the material where the particle is located, obtain the first material cross-section value corresponding to the first material energy node and the second material cross-section value corresponding to the second material energy node.

[0148] Step 606: Obtain the cross-sectional value of the material where the particle is located based on the particle energy, the first material energy node, the second material energy node, the first material cross-sectional value, and the second material cross-sectional value.

[0149] Specifically, for any given particle energy, within a pre-defined set of material energy nodes, a first material energy node and a second material energy node adjacent to the particle energy are determined, wherein the first material energy node is less than the particle energy, and the second material energy node is greater than the particle energy. From the material cross-section library corresponding to the material where the particle is located, the first material cross-section value corresponding to the first material energy node and the second material cross-section value corresponding to the second material energy node are obtained. Based on the calculation relationship between particle energy, the first material energy node, the second material energy node, the first material cross-section value, the second material cross-section value, and the cross-section value of the material where the particle is located, the cross-section value of the material where the particle is located is obtained.

[0150] Furthermore, step 606, obtaining the cross-sectional value of the material where the particle is located based on the particle energy, the first material energy node, the second material energy node, the first material cross-sectional value, and the second material cross-sectional value, includes: performing linear interpolation on the first material cross-sectional value and the second material cross-sectional value based on the particle energy, the first material energy node, and the second material energy node to obtain the cross-sectional value of the material where the particle is located.

[0151] Based on the calculation relationship between particle energy, first material energy node, second material energy node, first material cross-sectional value, second material cross-sectional value, and the cross-sectional value of the material in which the particle is located, the cross-sectional value of the material in which the particle is located is obtained. The calculation relationship of the cross-sectional value of the material in which the particle is located can be a linear interpolation calculation relationship, as shown below:

[0152] Where, ∑ t (E′) represents the cross-sectional value of the material where the particle is located, E′ represents the particle energy, and E1′ and E2′ represent the first and second material energy nodes, respectively. ∑ t (E1′) and ∑ t (E2′) represent the cross-sectional values ​​of the first and second materials, respectively.

[0153] Formula (5) has the same form as Formula (4), both of which use linear interpolation to calculate the cross-sectional value. However, Formula (5) calculates the cross-sectional value of the material in which the particle is located, i.e., the macroscopic cross-section, while Formula (4) calculates the cross-sectional value of the constituent nuclides, i.e., the microscopic cross-section.

[0154] Optionally, besides linear interpolation, the cross-sectional value of the material containing the particle can also be calculated using logarithmic interpolation or a quadratic function. Logarithmic interpolation can be divided into two cases: one is to perform logarithmic interpolation only on the cross-sectional values ​​of the first and second materials, as shown in the following formula:

[0155] Another approach involves logarithmic interpolation of the first material cross-sectional value, the second material cross-sectional value, the particle energy, the first material energy node, and the second material energy node, as shown in the following formula:

[0156] In this embodiment, by converting the nuclide cross-section library of constituent nuclides into a material cross-section library, the processor can directly obtain the cross-section values ​​corresponding to adjacent energy nodes in the material cross-section library during particle simulation calculations, thereby calculating the cross-section value of the material in which the particle is located. There is no need to calculate the cross-section values ​​of the constituent nuclides contained in the material, which greatly reduces the calculation time of material cross-section values ​​in dose calculation, improves the calculation efficiency of material cross-section values, and improves the efficiency of dose assessment.

[0157] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0158] Based on the same inventive concept, this application also provides a dose assessment system for implementing the dose assessment method described above. The solution provided by this device is similar to the implementation described in the above method; therefore, the specific limitations of the control device embodiments of one or more dose calculation systems provided below can be found in the limitations of the dose assessment method described above, and will not be repeated here.

[0159] In an exemplary embodiment, as shown in FIG7, a dose assessment system is provided, including a material cross-section library construction module 702, a particle simulation calculation module 704, and a dose assessment module 706. The material cross-section library construction module 702 includes a material energy node setting unit 7022, a material information acquisition unit 7024, and a material cross-section library construction unit 7026, wherein:

[0160] Material Section Library Construction Module 702 is used to construct a material section library for three-dimensional voxel models.

[0161] The particle simulation calculation module 704 is used to perform particle simulation calculations based on the material section library to obtain the cross-sectional value of the material in which the particle is located.

[0162] The dose assessment module 706 is used to assess the dose based on the cross-sectional value of the material in which the particle is located.

[0163] The material section library construction module 702 includes:

[0164] The material energy node setting unit 7022 is used to set the material energy node.

[0165] The material information acquisition unit 7024 is used to acquire the material information of the three-dimensional voxel model; the material information includes at least the constituent nuclides and the number density of nuclide particles.

[0166] Material section library construction unit 7026 is used to construct a material section library based on material energy nodes and material information.

[0167] In one exemplary embodiment, the material energy node setting unit 7022 includes:

[0168] The first energy node setting sub-unit is used to determine the minimum and maximum nuclide energy node values ​​among all the nuclide energy nodes based on the nuclide cross-section library of the constituent nuclides. The minimum nuclide energy node value is determined as the minimum material energy node, and the maximum nuclide energy node value is determined as the maximum material energy node.

[0169] The second energy node setting sub-unit is used to set the material energy node based on the minimum material energy node and the maximum material energy node.

[0170] In one exemplary embodiment, the second energy node setting subunit includes:

[0171] The uniform logarithmic interpolation unit is used to uniformly logarithmically interpolate a preset number of energy intervals between the minimum and maximum material energy nodes to obtain the material energy nodes.

[0172] In one exemplary embodiment, the second energy node setting subunit includes:

[0173] The uniform logarithmic interpolation unit is used to uniformly logarithmically interpolate a preset number of energy intervals between the minimum and maximum material energy nodes to obtain the energy nodes after uniform logarithmic interpolation.

[0174] The resonance node determination unit is used to determine the resonance energy nodes of the constituent nuclides based on the nuclide cross-section library of the constituent nuclides.

[0175] The resonant node addition unit is used to add the resonant energy nodes of the constituent nuclides to the energy nodes after uniform logarithmic interpolation, thereby obtaining the material energy nodes.

[0176] In one exemplary embodiment, the resonance node determination unit includes:

[0177] The continuous nuclide cross-section value acquisition unit is used to acquire the nuclide cross-section values ​​of the constituent nuclides at multiple consecutive nuclide energy nodes based on the nuclide cross-section library of the constituent nuclides.

[0178] The resonance identification unit is used to identify whether a constituent nuclide has a peak or a trough based on the nuclide cross-sectional values ​​at multiple consecutive nuclide energy nodes.

[0179] The resonance node determination unit is used to determine multiple consecutive nuclide energy nodes as the resonance energy nodes of the constituent nuclide when the existence of peaks or troughs is identified.

[0180] In one exemplary embodiment, the material section library construction unit includes:

[0181] The nuclide cross-section value determination sub-unit is used to determine the nuclide cross-section value of the constituent nuclide corresponding to the material energy node based on the nuclide cross-section library of the constituent nuclides.

[0182] The material cross-section value determination sub-unit is used to determine the material cross-section value of the material energy node based on the nuclide cross-section value and the nuclide particle number density corresponding to the material energy node.

[0183] The material section library construction sub-unit is used to construct the material section library based on material energy nodes and material section values.

[0184] In one exemplary embodiment, the nuclide cross-section value determining sub-unit includes:

[0185] The nuclide energy node identification unit is used to identify whether a material energy node is a nuclide energy node of the nuclide cross-section library that makes up the nuclide.

[0186] The first nuclide cross-section value acquisition unit is used to acquire the nuclide cross-section value corresponding to the nuclide energy node as the nuclide cross-section value corresponding to the material energy node if the material energy node is the nuclide energy node of the nuclide cross-section library that makes up the nuclide.

[0187] The second nuclide cross-section value acquisition unit is used to acquire, if the material energy node is not a nuclide energy node in the nuclide cross-section library that is adjacent to the material energy node, wherein the first nuclide energy node is smaller than the second nuclide energy node, and to acquire the first nuclide cross-section value corresponding to the first nuclide energy node and the second nuclide cross-section value corresponding to the second nuclide energy node. The unit determines the nuclide cross-section value of the constituent nuclide corresponding to the material energy node based on the material energy node, the first nuclide energy node, the second nuclide energy node, the first nuclide cross-section value and the second nuclide cross-section value.

[0188] In an exemplary embodiment, the second nuclide cross-section value acquisition unit includes:

[0189] The first linear interpolation unit is used to perform linear interpolation on the cross-sectional values ​​of the first and second nuclides based on the material energy node, the first nuclide energy node, and the second nuclide energy node, so as to obtain the nuclide cross-sectional values ​​of the constituent nuclides corresponding to the material energy node.

[0190] In one exemplary embodiment, the particle simulation calculation module includes:

[0191] The adjacent energy node determination unit is used to determine the first material energy node and the second material energy node adjacent to the particle energy based on the material energy node; the first material energy node is less than the particle energy, and the second material energy node is greater than the particle energy.

[0192] The material cross-section value acquisition unit is used to acquire the first material cross-section value corresponding to the first material energy node and the second material cross-section value corresponding to the second material energy node from the material cross-section library corresponding to the material where the particle is located.

[0193] The particle simulation calculation unit is used to obtain the cross-sectional value of the material where the particle is located based on the particle energy, the first material energy node, the second material energy node, the first material cross-sectional value, and the second material cross-sectional value.

[0194] In one exemplary embodiment, the particle simulation computing unit includes:

[0195] The second linear interpolation unit is used to perform linear interpolation on the first material cross-sectional value and the second material cross-sectional value based on the particle energy, the first material energy node, and the second material energy node, so as to obtain the cross-sectional value of the material where the particle is located.

[0196] Each module or unit in the control device of the aforementioned dose calculation system can be implemented entirely or partially through software, hardware, or a combination thereof. These modules or units can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0197] In one embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram is shown in Figure 8. The computer device includes a processor, memory, input / output interface, communication interface, display unit, and input device. The processor, memory, and input / output interface are connected via a system bus, and the communication interface, display unit, and input device are also connected to the system bus via the input / output interface. The processor of the computer device provides computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The input / output interface of the computer device is used for exchanging information between the processor and external devices. The communication interface of the computer device is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, mobile cellular networks, NFC (Near Field Communication), or other technologies. When the computer program is executed by the processor, it implements a method for constructing a material cross-section library or a dose assessment method. The display unit of the computer device is used to form a visually visible image and may be a display screen, a projection device, or a virtual reality imaging device. The display screen can be an LCD screen or an e-ink screen. The input device of the computer device can be a touch layer covering the display screen, or buttons, trackballs, or touchpads set on the casing of the computer device, or external keyboards, touchpads, or mice, etc.

[0198] Those skilled in the art will understand that the structure shown in Figure 8 is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or may combine certain components, or may have different component arrangements.

[0199] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above-described method embodiments.

[0200] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps in the above method embodiments.

[0201] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0202] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0203] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0204] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for constructing a material cross-section library, characterized in that, The method includes: Set up material energy nodes; Obtain material information; the material information includes at least: constituent nuclides and nuclide particle number density; A material cross-section library is constructed based on the material energy nodes and the material information.

2. The construction method according to claim 1, characterized in that, The setting of material energy nodes includes: Based on the nuclide cross-section library of the constituent nuclides, the minimum and maximum nuclide energy node values ​​among all the nuclide energy nodes are determined. The minimum nuclide energy node value is determined as the minimum material energy node, and the maximum nuclide energy node value is determined as the maximum material energy node. The material energy node is set according to the minimum material energy node and the maximum material energy node.

3. The construction method according to claim 2, characterized in that, The step of setting the material energy node based on the minimum material energy node and the maximum material energy node includes: The material energy node is obtained by uniformly logarithmically interpolating a preset number of energy intervals between the minimum material energy node and the maximum material energy node.

4. The construction method according to claim 2, characterized in that, The step of setting the material energy node based on the minimum material energy node and the maximum material energy node includes: A preset number of energy intervals are uniformly logarithmically interpolated between the minimum material energy node and the maximum material energy node to obtain the energy node after uniform logarithmic interpolation; Based on the nuclide cross-section library of the constituent nuclides, the resonance energy nodes of the constituent nuclides are determined; The resonant energy nodes of the constituent nuclides are added to the energy nodes after uniform logarithmic interpolation to obtain the material energy nodes.

5. The construction method according to claim 4, characterized in that, The determination of the resonance energy nodes of the constituent nuclides based on the nuclide cross-section library includes: Based on the nuclide cross-section library of the constituent nuclides, the nuclide cross-section values ​​of the constituent nuclides at multiple consecutive nuclide energy nodes are obtained; Based on the nuclide cross-sectional values ​​of the constituent nuclide at multiple consecutive nuclide energy nodes, identify whether the constituent nuclide has peaks or troughs; When the constituent nuclide is identified to have a peak or trough, the corresponding multiple consecutive nuclide energy nodes are determined as the resonance energy nodes of the constituent nuclide.

6. The construction method according to claim 1, characterized in that, The construction of the material cross-section library based on the material energy node and the material information includes: Based on the nuclide cross-section library of the constituent nuclides, determine the nuclide cross-section value of the constituent nuclide corresponding to the material energy node; The material cross-sectional value of the material energy node is determined based on the nuclide cross-sectional value corresponding to the constituent nuclide and the nuclide particle number density. A material cross-section library is constructed based on the material energy nodes and the material cross-section values.

7. The construction method according to claim 6, characterized in that, The step of determining the nuclide cross-section value of the constituent nuclide corresponding to the material energy node based on the nuclide cross-section library includes: Identify whether the material energy node is a nuclide energy node of the nuclide cross section library that constitutes the nuclide; If the material energy node is a nuclide energy node in the nuclide cross-section library of the constituent nuclide, then the nuclide cross-section value corresponding to the nuclide energy node is obtained as the nuclide cross-section value of the constituent nuclide corresponding to the material energy node; If the material energy node is not a nuclide energy node in the nuclide cross-section library of the constituent nuclide, then the first nuclide energy node and the second nuclide energy node adjacent to the material energy node in the nuclide cross-section library are obtained, wherein the first nuclide energy node is smaller than the second nuclide energy node, and the first nuclide cross-section value corresponding to the first nuclide energy node and the second nuclide cross-section value corresponding to the second nuclide energy node are obtained. The nuclide cross-section value of the constituent nuclide corresponding to the material energy node is determined based on the material energy node, the first nuclide energy node, the second nuclide energy node, the first nuclide cross-section value, and the second nuclide cross-section value.

8. A dosage assessment method, characterized in that, The method includes: Set up material energy nodes; Obtain material information for a three-dimensional voxel model; the material information includes at least: constituent nuclides and nuclide particle number density; A material cross-section library is constructed based on the material energy nodes and the material information; Particle simulation calculations are performed based on the material cross-section library to obtain the cross-sectional value of the material in which the particle is located; the dose is evaluated based on the cross-sectional value of the material in which the particle is located.

9. The dosage assessment method according to claim 8, characterized in that, The step of performing particle simulation calculations based on the material cross-section library to obtain the cross-sectional value of the material where the particle is located includes: Based on the material energy nodes, a first material energy node and a second material energy node adjacent to the particle energy are determined; the first material energy node is less than the particle energy, and the second material energy node is greater than the particle energy; In the material cross-section library corresponding to the material where the particle is located, obtain the first material cross-section value corresponding to the first material energy node and the second material cross-section value corresponding to the second material energy node; The cross-sectional value of the material where the particle is located is obtained based on the particle energy, the first material energy node, the second material energy node, the first material cross-sectional value, and the second material cross-sectional value.

10. A dose assessment system, characterized in that, include: The Material Section Library Construction Module is used to build a material section library for 3D voxel models. The particle simulation calculation module is used to perform particle simulation calculations based on the material section library to obtain the section value of the material where the particle is located. The dose assessment module is used to assess the dose based on the cross-sectional value of the material in which the particle is located; The material section library construction module includes: Material energy node setting unit, used to set material energy nodes; A material information acquisition unit is used to acquire material information of a three-dimensional voxel model; the material information includes at least: constituent nuclides and nuclide particle number density; The material section library construction unit is used to construct a material section library based on the material energy node and the material information.

11. The dose assessment system according to claim 10, characterized in that, The material energy node setting unit includes: The first energy node setting subunit is used to determine the minimum and maximum nuclide energy node values ​​among all the nuclide energy nodes based on the nuclide cross-section library of the constituent nuclides, and to determine the minimum nuclide energy node value as the minimum material energy node and the maximum nuclide energy node value as the maximum material energy node. The second energy node setting subunit is used to set the material energy node according to the minimum material energy node and the maximum material energy node.

12. The dose assessment system according to claim 11, characterized in that, The second energy node setting subunit includes: A uniform logarithmic interpolation unit is used to uniformly logarithmically interpolate a preset number of energy intervals between the minimum material energy node and the maximum material energy node to obtain the energy node after uniform logarithmic interpolation. A resonance node determination unit is used to determine the resonance energy node of the constituent nuclide based on the nuclide cross-section library of the constituent nuclide. A resonance node adding unit is used to add the resonance energy nodes of the constituent nuclides to the energy nodes after uniform logarithmic interpolation to obtain the material energy nodes.

13. The dose assessment system according to claim 10, characterized in that, The material section library construction unit includes: The nuclide cross-section value determination subunit is used to determine the nuclide cross-section value of the constituent nuclide corresponding to the material energy node based on the nuclide cross-section library of the constituent nuclides. The material cross-section value determination subunit is used to determine the material cross-section value of the material energy node based on the nuclide cross-section value of the constituent nuclide corresponding to the material energy node and the nuclide particle number density; A material section library construction subunit is used to construct a material section library based on the material energy node and the material section value.

14. The dose assessment system according to claim 13, characterized in that, The nuclide cross-section value determination sub-unit includes: A nuclide energy node identification unit is used to identify whether the material energy node is a nuclide energy node of the nuclide cross-section library that constitutes the nuclide; The first nuclide cross-section value acquisition unit is used to acquire the nuclide cross-section value corresponding to the nuclide energy node as the nuclide cross-section value corresponding to the material energy node if the material energy node is a nuclide energy node in the nuclide cross-section library of the constituent nuclide. The second nuclide cross-section value acquisition unit is configured to, if the material energy node is not a nuclide energy node in the nuclide cross-section library of the constituent nuclide, acquire a first nuclide energy node and a second nuclide energy node adjacent to the material energy node in the nuclide cross-section library, wherein the first nuclide energy node is smaller than the second nuclide energy node, and acquire a first nuclide cross-section value corresponding to the first nuclide energy node and a second nuclide cross-section value corresponding to the second nuclide energy node, and determine the nuclide cross-section value of the constituent nuclide corresponding to the material energy node based on the material energy node, the first nuclide energy node, the second nuclide energy node, the first nuclide cross-section value and the second nuclide cross-section value.

15. The dose assessment system according to claim 10, characterized in that, The particle simulation calculation module includes: An adjacent energy node determination unit is used to determine a first material energy node and a second material energy node adjacent to the particle energy based on the material energy node; the first material energy node is less than the particle energy, and the second material energy node is greater than the particle energy; The material cross-section value acquisition unit is used to acquire the first material cross-section value corresponding to the first material energy node and the second material cross-section value corresponding to the second material energy node from the material cross-section library corresponding to the material where the particle is located; The particle simulation calculation unit is used to obtain the cross-sectional value of the material where the particle is located based on the particle energy, the first material energy node, the second material energy node, the first material cross-sectional value, and the second material cross-sectional value.

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