基于马尔可夫链与EASI模型的核材料实物保护效能评估

Evaluation of physical protection effectiveness of nuclear materials based on Markov chain and EASI model

中国是世界上在建核电机组数量最多的国家,未来中国的核电发电量将会逐渐占据更高的发电比例,随着犯罪人员技术手段的升级,提升实物保护PPS(Physical Protection Systems)的防护效能、保障核设施安全运转至关重要。本文从分析防护系统关键节点入手,提出一种基于马尔可夫链与敌手入侵中断评估EASI(Estimation of Adversary Sequence Interruption)模型的核材料实物保护效能评估方法,考虑到PPS防护节点的关键性,以最低的代价提升整体防护性能;最后,通过在国际原子能机构研究所公开的场景和数据上进行评估计算,找到关键节点,采取特定的针对措施提升节点的效能,在提高PPS的防护性能的同时很大的程度上节约成本。实验发现:关键节点改进后,PPS系统最薄弱路径中断概率可提升4.12个百分点;全路径中断概率最少提升0.3个百分点,最大提升5.37个百分点;中断概率平均提升2.78个百分点。本文研究成果可以为核材料实物保护系统的升级提供参考和建议。

Currently,China has the largest number of nuclear power units under construction in the world.In the future,China’s nuclear power generation will gradually account for a higher proportion of power generation.With the upgrading of criminal technology,it is of great importance to improve the Protection efficiency of PPS(Physical Protection Systems)and ensure the safe operation of nuclear facilities.In this paper,an evaluation method of physical protection efficiency of nuclear materials based on Markov chain and EASI(Estimation of Adversary Sequence Interruption)model is proposed based on the analysis of key nodes of the defense system.This method considers the criticality of PPS protection nodes.The overall protection performance can be upgraded with the minimum efficiency ratio.Finally,the key nodes can be found through the evaluation and calculation on the scenarios and data made public by the IAEA institute,and specific measures can be taken to improve the efficiency of the nodes.The PPS protection performance can be improved and the cost can be saved to a great extent.The results show that the probability of the weakest path interruption increases by 4.12 percentage points,the probability of the whole path interruption increases by 0.3 percentage points and 5.37 percentage points,and the probability of interruption increases by 2.78 percentage points on average.The results of this study can provide references and suggestions for the upgrade of the nuclear material physical protection system.