Research On Protection Strategy Model For Persistent Attacks In Counter Terrorism Game

The security issues have always been the focus of all countries in the world.Terrorist organizations can choose to attack in a variety of ways.Although the security department may have a certain understanding of terrorist organizations' activities,due to the limited amount of information that the security department has,it is difficult to accurately predict which targets will be attacked and which ways will be chosen to attack.At the same time,security resources owned by the security department are limited and cannot protect all potential targets during 24 hours.Therefore,how to properly deploy limited security resources is an urgent problem for the security department.There are still many challenges that are difficult to overcome in the Anti-terrorism.In recent years,many terrorist attacks have demonstrated persistent.That is,terrorists may continue to pose a life threat to the people with killing weapons.They may also carry out multiple terrorist attacks in a short period of time.However,most of the existing studies have neglected these issues.For the persistent attacks of terrorists,this paper first models it as a novel Stackelberg game.Next,this paper proposes a compact representation of the mathematical program to solve the optimal protection strategy of the security department.Finally,in order to further improve the scalability of the algorithm,this paper presents a based Double Oracle heuristic algorithm and proves the approximate ratio between it and the exact solution.Since terrorist attacks may be a premeditated serial attacks,it is also necessary to consider crowd evacuation after the attack.In response to the problem of crowd evacuation in the process of terrorist attacks,this paper also models it as a novel Stackelberg game.In this game,the security department need first allocate the crowd to the transportation network maximally,and then allocate limited security resources to protect crowd evacuation.And terrorists will carry out multiple attacks to stop the evacuation of the crowd.According to whether the evacuation process of the crowd is related to the time in the transportation network,this paper provides four algorithms for calculating the optimal protection strategy of the security department in different situations.This paper evaluates the proposed models and algorithms through a large number of experiments.The experimental results show that the model and algorithms proposed in this paper are obviously superior to other baseline algorithms for the persistent attacks of terrorists,and the proposed heuristic algorithms further improves the scalability.For the problem of crowd evacuation in terrorist attacks,the algorithms proposed in this paper are obviously better than the random algorithm,and this paper compares the proposed four algorithms in different graph structures.