In order to find a method which can describe the passenger flow dynamical distribution of urban mass transit during interval interrupted operation,an urban railway network topology model was built based on the travel ...In order to find a method which can describe the passenger flow dynamical distribution of urban mass transit during interval interrupted operation,an urban railway network topology model was built based on the travel path dual graph by considering interchange,crowd and congestion.The breadth first valid travel path search algorithm is proposed,and the multipath passenger flow distribution logit model is improved.According to the characteristics of passengers under the interruption condition,the distribution rules of different types of passenger flow are proposed.The method of calculating the aggregation number of station is proposed for the case of insufficient transport capacity.Finally,the passenger flow of Beijing urban mass transit is simulated for the case study.The results show that the relative error of most of transfer passenger flow is below 10%.The proposed model and algorithm can accurately assign the daily passenger flow,which provides a theoretical basis for urban mass transit emergency management and decision.展开更多
The evolutionary dynamics first conceived by Darwin and Wallace, referring to as Darwinian dynamics in the present paper, has been found to be universally valid in biology. The statistical mechanics and thermodynamics...The evolutionary dynamics first conceived by Darwin and Wallace, referring to as Darwinian dynamics in the present paper, has been found to be universally valid in biology. The statistical mechanics and thermodynamics, while enormous successful in physics, have been in an awkward situation of wanting a consistent dynamical understanding. Here we present from a formal point of view an exploration of the connection between thermodynamics and Darwinian dynamics and a few related topics. We first show that the stochasticity in Darwinian dynamics implies the existence temperature, hence the canonical distribution of Boltzmann-Gibbs type. In term of relative entropy the Second Law of thermodynamics is dynamically demonstrated without detailed balance condition, and is valid regardless of size of the system. In particular, the dynamical component responsible for breaking detailed balance condition does not contribute to the change of the relative entropy. Two types of stochastic dynamical equalities of current interest are explicitly discussed in the present approach: One is based on Feynman-Kac formula and another is a generalization of Einstein relation. Both are directly accessible to experimental tests. Our demonstration indicates that Darwinian dynamics represents logically a simple and straightforward starting point for statistical mechanics and thermodynamics and is complementary to and consistent with conservative dynamics that dominates the physical sciences. Present exploration suggests the existence of a unified stochastic dynamical framework both near and far from equilibrium.展开更多
基金The National Natural Science Foundation of China(No.61374157)the Science and Technology Project of the Education Department of Jiangxi Province(No.GJJ151524)
文摘In order to find a method which can describe the passenger flow dynamical distribution of urban mass transit during interval interrupted operation,an urban railway network topology model was built based on the travel path dual graph by considering interchange,crowd and congestion.The breadth first valid travel path search algorithm is proposed,and the multipath passenger flow distribution logit model is improved.According to the characteristics of passengers under the interruption condition,the distribution rules of different types of passenger flow are proposed.The method of calculating the aggregation number of station is proposed for the case of insufficient transport capacity.Finally,the passenger flow of Beijing urban mass transit is simulated for the case study.The results show that the relative error of most of transfer passenger flow is below 10%.The proposed model and algorithm can accurately assign the daily passenger flow,which provides a theoretical basis for urban mass transit emergency management and decision.
基金The project supported in part by USA NIH Grant under HG002894
文摘The evolutionary dynamics first conceived by Darwin and Wallace, referring to as Darwinian dynamics in the present paper, has been found to be universally valid in biology. The statistical mechanics and thermodynamics, while enormous successful in physics, have been in an awkward situation of wanting a consistent dynamical understanding. Here we present from a formal point of view an exploration of the connection between thermodynamics and Darwinian dynamics and a few related topics. We first show that the stochasticity in Darwinian dynamics implies the existence temperature, hence the canonical distribution of Boltzmann-Gibbs type. In term of relative entropy the Second Law of thermodynamics is dynamically demonstrated without detailed balance condition, and is valid regardless of size of the system. In particular, the dynamical component responsible for breaking detailed balance condition does not contribute to the change of the relative entropy. Two types of stochastic dynamical equalities of current interest are explicitly discussed in the present approach: One is based on Feynman-Kac formula and another is a generalization of Einstein relation. Both are directly accessible to experimental tests. Our demonstration indicates that Darwinian dynamics represents logically a simple and straightforward starting point for statistical mechanics and thermodynamics and is complementary to and consistent with conservative dynamics that dominates the physical sciences. Present exploration suggests the existence of a unified stochastic dynamical framework both near and far from equilibrium.