基于非均匀源活度分布反演的γ辐射场重构方法  

Radiation field reconstruction method based on non-uniform source activity distribution inversion

作　　者：刘立业[1] 樊清 李华 李会 靳海晶 赵原[1,2] LIU Liye;FAN Qing;LI Hua;LI Hui;JIN Haijing;ZHAO Yuan(China Institute for Radiation Protection,Taiyuan 030006,China;Shanxi Key Laboratory for Radiation Safety and Protection,Taiyuan 030006,China)

机构地区：[1]中国辐射防护研究院,太原030006 [2]辐射安全与防护山西省重点实验室,太原030006

出　　处：《核技术》2025年第4期80-89,共10页Nuclear Techniques

基　　金：中核集团"青年英才"菁英项目(No.29,No.69);山西省科技创新领军人才团队项目资助。

摘　　要：辐射场的准确重构是实现辐射防护数字化的基础,也是进行辐射剂量评估与可视化仿真的前提。为了有效解决目前核设施现场由于高梯度非均匀辐射源项分布导致的三维γ辐射场重构偏差较大的切实问题,本文创新性地提出基于贝叶斯信息准则建立的非均匀源活度分布模型择优方法,并将最优模型用于三维γ辐射场的重构。结果表明:该方法在高活度梯度、高剂量率梯度情形下的辐射场重构准确度显著优于克里金插值方法;在核设施实际场景的三维辐射场重构案例中,测试集剂量率重构结果与实测值平均相对偏差仅为12.69%,低于克里金插值结果的85.40%。本研究可为核设施现场基于动态数据驱动的辐射防护数字化仿真工作提供先进技术支撑,增强其在实际应用中的效果。[Background]The accurate reconstruction ofγradiation fields is fundamental to the digitalization of radiation protection and is a prerequisite for radiation dose assessment and visualization simulation.Traditional interpolation methods and uniform source activity inversion methods struggle to accurately reconstruct high-dose-rate gradient 3D radiation fields in scenarios with high-gradient,non-uniform activity distributions within large volume source terms inside nuclear facilities.[Purpose]This study aims to develop an inversion method for non-uniform source activity distribution and apply it to accurately reconstruct 3D gamma radiation fields of the aforementioned types.[Methods]Based on multi-objective source activity inversion and the Bayesian Information Criterion,an innovative inversion method for non-uniform source activity distribution was proposed.Then,the accuracy of radiation field reconstruction results in a pipeline simulation case obtained by using this method and ordinary Kriging interpolation method were compared under different source activity distribution conditions in various regions.Finally,the effectiveness of this method was further validated using measured data from inside a nuclear facility.[Results]Under four different activity distribution conditions in the pipeline simulation case,the proposed method achieves an ARD(average relative deviation)of less than 5%for radiation field reconstruction results in all regions,significantly outperforming the ordinary Kriging interpolation method,especially in high-dose-rate gradient areas.In the real nuclear facility scenario,the ARD between 77 reconstructed dose rate values calculated from 30 measured values and the actual measurements is only 12.69%,much lower than the result of 85.40%by ordinary Kriging interpolation.[Conclusions]The inversion of non-uniform source activity distribution achieved by introducing the Bayesian Information Criterion in this study is very suitable for gamma radiation field reconstruction under complex source term cond

关 键 词：三维辐射场 源活度反演 非均匀分布 信息准则 辐射防护 

分 类 号：TL72[核科学技术—辐射防护及环境保护]