The study of mathematical models for the spread of infectious diseases is an important issue in epidemiology. Given the fact that most existing models cannot comprehensively depict heterogeneities (e.g., the populatio...The study of mathematical models for the spread of infectious diseases is an important issue in epidemiology. Given the fact that most existing models cannot comprehensively depict heterogeneities (e.g., the population heterogeneity and the distribution heterogeneity) and complex contagion patterns (which are mostly caused by the human interaction induced by modern transportation) in the real world, a theoretical model of the spread of infectious diseases is proposed. It employs geo-entity based cel-lular automata to simulate the spread of infectious diseases in a geographical environment. In the model, physical geographical regions are defined as cells. The population within each cell is divided into three classes: Susceptible, Infective, and Recovered, which are further divided into some sub-classes by states of individuals. The transition rules, which determine the changes of proportions of those subclasses and reciprocal transformation formulas among them, are provided. Through defining suitable spatial weighting functions, the model is applied to simulate the spread of the infectious dis-eases with not only local contagion but also global contagion. With some cases of simulation, it has been shown that the results are reasonably consistent with the spread of infectious diseases in the real world. The model is supposed to model dynamics of infectious diseases on complex networks, which is nearly impossible to be achieved with differential equations because of the complexity of the prob-lem. The cases of simulation also demonstrate that efforts of all kinds of interventions can be visual-ized and explored, and then the model is able to provide decision-making support for prevention and control of infectious diseases.展开更多
The seriousness of losses caused by disaster dependent on the hazard degree of environment,vulnerability of hazard-affected bodies,and emergency response capacity of the region is studied in this article.The study on ...The seriousness of losses caused by disaster dependent on the hazard degree of environment,vulnerability of hazard-affected bodies,and emergency response capacity of the region is studied in this article.The study on hazard-affected bodies is of importance to disaster risk management,regional hazard prevention,reduction,and investment in disaster insurance.With summarizing of various assessment methods of vulnerability of hazard-affected bodies,this paper presents a refined Spatial Quantification Model of regional vulnerability which combines refined spatial geographic data and land-use type data.A quantitative study on regional vulnerability was carried out by defining fine spatial grid as the basic evaluation unit based on GIS.展开更多
基金Supported by Postdoctoral Foundation of China (Grant No. 20070410552)Youth Fund of Institute of Policy and Management (IPM), the Chinese Academy of Sci-ences (Grant No. O700481Q01)
文摘The study of mathematical models for the spread of infectious diseases is an important issue in epidemiology. Given the fact that most existing models cannot comprehensively depict heterogeneities (e.g., the population heterogeneity and the distribution heterogeneity) and complex contagion patterns (which are mostly caused by the human interaction induced by modern transportation) in the real world, a theoretical model of the spread of infectious diseases is proposed. It employs geo-entity based cel-lular automata to simulate the spread of infectious diseases in a geographical environment. In the model, physical geographical regions are defined as cells. The population within each cell is divided into three classes: Susceptible, Infective, and Recovered, which are further divided into some sub-classes by states of individuals. The transition rules, which determine the changes of proportions of those subclasses and reciprocal transformation formulas among them, are provided. Through defining suitable spatial weighting functions, the model is applied to simulate the spread of the infectious dis-eases with not only local contagion but also global contagion. With some cases of simulation, it has been shown that the results are reasonably consistent with the spread of infectious diseases in the real world. The model is supposed to model dynamics of infectious diseases on complex networks, which is nearly impossible to be achieved with differential equations because of the complexity of the prob-lem. The cases of simulation also demonstrate that efforts of all kinds of interventions can be visual-ized and explored, and then the model is able to provide decision-making support for prevention and control of infectious diseases.
基金funded by the Science and Technology project of the Meteorological Bureau of Zhejiang Province in 2010(No.2010ZD05)Science and Technology projects in Zhejiang Province(No.2007C33062).
文摘The seriousness of losses caused by disaster dependent on the hazard degree of environment,vulnerability of hazard-affected bodies,and emergency response capacity of the region is studied in this article.The study on hazard-affected bodies is of importance to disaster risk management,regional hazard prevention,reduction,and investment in disaster insurance.With summarizing of various assessment methods of vulnerability of hazard-affected bodies,this paper presents a refined Spatial Quantification Model of regional vulnerability which combines refined spatial geographic data and land-use type data.A quantitative study on regional vulnerability was carried out by defining fine spatial grid as the basic evaluation unit based on GIS.
