在传统对象Petri网中引入函数的概念,定义了一种全新的生态系统脆弱性评价模型OFPNEM(Object Function Petri Net Model),将对生态系统恶化过程中起促进与抑制作用的两方面因素进行综合考虑与分析。用变迁表示脆弱程度的触发条件,用对...在传统对象Petri网中引入函数的概念,定义了一种全新的生态系统脆弱性评价模型OFPNEM(Object Function Petri Net Model),将对生态系统恶化过程中起促进与抑制作用的两方面因素进行综合考虑与分析。用变迁表示脆弱程度的触发条件,用对象库所表示生态系统变化过程中所处的状态,从而直观地表示生态环境恶化的逻辑因果关系,提出了一种基于对象函数Petri网的矿区生态系统脆弱性评价模型OFPNEM。在对象函数Petri网基础上,结合模型原理的规则,给出OFPNEM算法,并通过实验验证了算法的正确性。通过对象函数Petri网对具有动态变化过程的矿区生态系统脆弱性评价,更加贴近实际情况。展开更多
The remain passenger problem at subway station platform was defined initially,and the period variation of remain passenger queues at platform was investigated through arriving and boarding analyses.Taking remain passe...The remain passenger problem at subway station platform was defined initially,and the period variation of remain passenger queues at platform was investigated through arriving and boarding analyses.Taking remain passenger queues at platform as dynamic stochastic process,a new probabilistic queuing method was developed based on probabilistic theory and discrete time Markov chain theory.This model can calculate remain passenger queues while considering different directions.Considering the stable or variable train arriving period and different platform crossing types,a series of model deformation research was carried out.The probabilistic approach allows to capture the cyclic behavior of queues,measures the uncertainty of a queue state prediction by computing the evolution of its probability in time,and gives any temporal distribution of the arrivals.Compared with the actual data,the deviation of experimental results is less than 20%,which shows the efficiency of probabilistic approach clearly.展开更多
文摘在传统对象Petri网中引入函数的概念,定义了一种全新的生态系统脆弱性评价模型OFPNEM(Object Function Petri Net Model),将对生态系统恶化过程中起促进与抑制作用的两方面因素进行综合考虑与分析。用变迁表示脆弱程度的触发条件,用对象库所表示生态系统变化过程中所处的状态,从而直观地表示生态环境恶化的逻辑因果关系,提出了一种基于对象函数Petri网的矿区生态系统脆弱性评价模型OFPNEM。在对象函数Petri网基础上,结合模型原理的规则,给出OFPNEM算法,并通过实验验证了算法的正确性。通过对象函数Petri网对具有动态变化过程的矿区生态系统脆弱性评价,更加贴近实际情况。
基金Project(2011BAG01B01) supported by the Major State Basic Research and Development Program of ChinaProject(RCS2012ZZ002) supported by the State Key Lab of Rail Traffic Control and Safety,China
文摘The remain passenger problem at subway station platform was defined initially,and the period variation of remain passenger queues at platform was investigated through arriving and boarding analyses.Taking remain passenger queues at platform as dynamic stochastic process,a new probabilistic queuing method was developed based on probabilistic theory and discrete time Markov chain theory.This model can calculate remain passenger queues while considering different directions.Considering the stable or variable train arriving period and different platform crossing types,a series of model deformation research was carried out.The probabilistic approach allows to capture the cyclic behavior of queues,measures the uncertainty of a queue state prediction by computing the evolution of its probability in time,and gives any temporal distribution of the arrivals.Compared with the actual data,the deviation of experimental results is less than 20%,which shows the efficiency of probabilistic approach clearly.
