Risk Analysis of Urban Dirty Bomb Attacking Based on Bayesian Network

Abstract

Urban dirty bomb attacking is a type of unconventional terrorism threatening the urban security all through the world. In this paper, a Bayesian network of urban dirty bomb attacking is established to analyze the risk of urban dirty bomb attacking. The impacts of factors such as occurrence time, location, wind fields, the size of dirty bomb, emergency response and defense approaches on casualty from both direct blast and radiation-caused cancers are examined. Results show that sensitivity of casualty from cancers to wind fields are less significant; the impact of emergency response on the direct casualty from blast is not large; the size of the dirty bomb results in more casualties from cancers than that from bomb explosions; Whether an attack is detected by the police is not that related to normal or special time, but significantly depends on the attack location; Furthermore, casualty from cancers significantly depends on the location, while casualty from blast is not considerably influenced by the attacking location; patrol and surveillance are less important than security check in terms of controlling the risk of urban dirt bomb, and security check is the most effective approach to decreasing the risk of urban dirty bomb.

Modeling and Risk Analysis of Chemical Terrorist Attacks: A Bayesian Network Method

“…The probability of failure is low in scenario 7, 8, and 9, where the lowest one is 25%. Since Target C is in an open area, the probability of effective early warning is low, so the attack is more likely to succeed [56]. We can infer that terrorist organisations with different threat levels have a limit impact on the success of the attack, while the police prevention in different locations has a more significant impact.…”

“…The same conclusion also emerges in the defense methods for controlling the risk of urban dirty bomb attacks. Compared with patrol and surveillance, security inspections are more important and effective [56]. Because Target A lacks "Police investigation" and does not have "security check", the probability of "High" in node G dropped from 0.98 to 0.13.…”

“…The impact of emergency response capabilities on casualties are more significant than terrorist organisations of different threat levels. One of the reasons is that node I is not directly connected to node K. However, rather than reducing the direct casualties, emergency response is more significant in conducting rescue operations, reducing disasters such as continuous chemical pollution caused by chemical substances, moving casualties from contaminated environment to well-ventilated area to give first aid [1], and reducing the possibility of secondary attacks [40,56]. These measures ultimately reduced casualties.…”

“…Therefore, we added the node and divide it into four categories: large, medium, small and unknown. The dose of chemical weapons directly affects the level of bomb explosions and casualties [56]. 17.…”

“…In the case study, chemical terrorist attacks may have occurred in three different types, namely "commercial area", "residential area" and "open space". Obviously, different places have different requirements for defensive forces [38,42,56]. 21.…”