The most recent trends in population dynamics have provoked a rigorous debate whether the private or the public pension insurance system should be predominant. The pay-as-you-go system is dominated by the state that g...The most recent trends in population dynamics have provoked a rigorous debate whether the private or the public pension insurance system should be predominant. The pay-as-you-go system is dominated by the state that guarantees its stability. Private pension insurance provides personal retirement accounts and proper ownership of the accumulated funds, but its sustainability during prolonged market crises and inadequate risk sharing are often questioned. In order to address this issue, this paper makes both an assessment and analysis of the arguments put forward in favor of the preservation of the pay-as-you-go system and a comparison of this system with some of the main characteristics of the private accounts system. This is the basis for seeking the objectively defined role of the pay-as-you-go system in the conditions of the market economy. A couple of conclusions that have been formulated might be of interest for the future improvement of the organization and management of pension insurance.展开更多
This paper describes a non-linear information dynamics model for integrated risk assessment of complex disaster system from an evolution perspective. According to the occurrence and evolution of natural disaster syste...This paper describes a non-linear information dynamics model for integrated risk assessment of complex disaster system from an evolution perspective. According to the occurrence and evolution of natural disaster system with complicated and nonlinear characteristics, a non-linear information dynamics mode is introduced based on the maximum flux principle during modeling process to study the integrated risk assessment of complex disaster system. Based on the non-equilibrium statistical mechanics method, a stochastic evolution equation of this system is established. The integrated risk assessment of complex disaster system can be achieved by giving reasonable weights of each evaluation index to stabilize the system. The new model reveals the formation pattern of risk grade and the dynamics law of evolution. Meanwhile, a method is developed to solve the dynamics evolution equations of complex system through the self-organization feature map algorithm. The proposed method has been used in complex disaster integrated risk assessment for 31 provinces, cities and autonomous regions in China mainland. The results have indicated that the model is objective and effective.展开更多
Mathematical models are increasingly being used in the evaluation of control strategies for infectious disease such as the vaccination program for the Human PapiUomavirus （HPV）. Here, an ordinary differential equati...Mathematical models are increasingly being used in the evaluation of control strategies for infectious disease such as the vaccination program for the Human PapiUomavirus （HPV）. Here, an ordinary differential equation （ODE） transmission dynamic model for HPV is presented and analyzed. Parameter values for a gender and risk structured model are estimated by calibrating the model around the known prevalence of infection. The effect on gender and risk sub-group prevalence induced by varying the epidemiological parameters are investigated. Finally, the outcomes of this model are applied using a classical mathematical method for calculating R0 in a heterogeneous mixing population. Estimates for R0 under various gender and mixing scenarios are presented.展开更多
文摘The most recent trends in population dynamics have provoked a rigorous debate whether the private or the public pension insurance system should be predominant. The pay-as-you-go system is dominated by the state that guarantees its stability. Private pension insurance provides personal retirement accounts and proper ownership of the accumulated funds, but its sustainability during prolonged market crises and inadequate risk sharing are often questioned. In order to address this issue, this paper makes both an assessment and analysis of the arguments put forward in favor of the preservation of the pay-as-you-go system and a comparison of this system with some of the main characteristics of the private accounts system. This is the basis for seeking the objectively defined role of the pay-as-you-go system in the conditions of the market economy. A couple of conclusions that have been formulated might be of interest for the future improvement of the organization and management of pension insurance.
基金supported by the National Twelfth Five-year Technology Support Projects of China (Grant Nos. 2009BAJ28B04, 2011BAK07B01,2011BAJ08B03, and 2011BAJ08B05)the National Natural Science Foundation of China (Grant No. 51208017)+1 种基金Beijing Postdoctoral Research Foundation (Grant No. 2012ZZ-17)China Postdoctoral Science Foundation Funded Project (Grant No. 2011M500199)
文摘This paper describes a non-linear information dynamics model for integrated risk assessment of complex disaster system from an evolution perspective. According to the occurrence and evolution of natural disaster system with complicated and nonlinear characteristics, a non-linear information dynamics mode is introduced based on the maximum flux principle during modeling process to study the integrated risk assessment of complex disaster system. Based on the non-equilibrium statistical mechanics method, a stochastic evolution equation of this system is established. The integrated risk assessment of complex disaster system can be achieved by giving reasonable weights of each evaluation index to stabilize the system. The new model reveals the formation pattern of risk grade and the dynamics law of evolution. Meanwhile, a method is developed to solve the dynamics evolution equations of complex system through the self-organization feature map algorithm. The proposed method has been used in complex disaster integrated risk assessment for 31 provinces, cities and autonomous regions in China mainland. The results have indicated that the model is objective and effective.
文摘Mathematical models are increasingly being used in the evaluation of control strategies for infectious disease such as the vaccination program for the Human PapiUomavirus （HPV）. Here, an ordinary differential equation （ODE） transmission dynamic model for HPV is presented and analyzed. Parameter values for a gender and risk structured model are estimated by calibrating the model around the known prevalence of infection. The effect on gender and risk sub-group prevalence induced by varying the epidemiological parameters are investigated. Finally, the outcomes of this model are applied using a classical mathematical method for calculating R0 in a heterogeneous mixing population. Estimates for R0 under various gender and mixing scenarios are presented.
