Research On Risk Assessment Of Regional Disaster Chain

These years, all disasters happens frequently, and evolving as chain structure, often lead to further harm impact than a single disaster event. More and more instances of disaster chain makes people realize that starting from the point of view of disaster chain, disaster risk can be more effective in pre-disaster preparedness and disaster handling. So, how to assess risk of disaster chain is a very urgent problem to be solved.Aiming at the risk assessment about disasters chain research also less, From the supply chain and accident chain, this paper sum up 2 models on chained risk assessment. Draw on these patterns, and propose a more appropriate chain risk assessment model for disaster chain assessment. And analyze regional environment on which disaster chain happen, construct a indexes system that describe influence factors of region disaster chain, put forward a risk assessment model of regional disaster chain, to calculate risk value. Composition factors of the model are:the probability of a disaster cause another; the loss of an event on a disaster chain; the influence intensity of a disaster cause another to other events, that is, edge's vulnerability; the mode of they measure risk of disaster chain together, that is, assess model. The biggest difference with other risk assessment models of single disaster is, introducing edge's vulnerability of network of disaster chain, can better reflect interaction degree of causing relationship between disaster events. An example is given, when a disaster occurs in a region, trigger a number of disaster chain based on regional characteristics, we use the model, measure each disaster chain risk, can get an order of disaster chain risk, then do some decision-making support for disaster warning, chain bread and disaster reduction.Aiming at disaster chain's vulnerability in above model, carry out a detailed analysis. In a network constituted by disaster chain, edge express a caused relationship between disaster events, it is to use the research findings of network invulnerability, that measure vulnerability of edge based on network topology. Therefore, vulnerability of edge is network's inherent properties, it shows the edge's weak degree in the whole network, reflects interaction of caused relationship between disaster events, is a macroparameter that can measure disaster chain's risk. The measure of edge's vulnerability is based on research of network's invulnerability, which is to find the weak link in the network. In disaster network, base on the particularity that nodes can't be removed in disaster network, edge's vulnerability is the weak link of the network. In the meanwhile, an algorithm is given to calculate the vulnerability of edge, taking snowstorm in 2008 for example, verify the effectiveness of this algorithm.