This study presents a mathematical model for optimal vaccination strategies in interconnected metropolitan areas,considering commuting patterns.It is a compartmental model with a vaccination rate for each city,acting ...This study presents a mathematical model for optimal vaccination strategies in interconnected metropolitan areas,considering commuting patterns.It is a compartmental model with a vaccination rate for each city,acting as a control function.The commuting patterns are incorporated through a weighted adjacency matrix and a parameter that selects day and night periods.The optimal control problem is formulated to minimize a functional cost that balances the number of hospitalizations and vaccines,including restrictions of a weekly availability cap and an application capacity of vaccines per unit of time.The key findings of this work are bounds for the basic reproduction number,particularly in the case of a metropolitan area,and the study of the optimal control problem.Theoretical analysis and numerical simulations provide insights into disease dynamics and the effectiveness of control measures.The research highlights the importance of prioritizing vaccination in the capital to better control the disease spread,as we depicted in our numerical simulations.This model serves as a tool to improve resource allocation in epidemic control across metropolitan regions.展开更多
As sea level rises,low-lying coastal cites face increasing threat of flood disruption,particularly in terms of human mobility.Commuters are vulnerable to bad weather,as it is difficult to cancel trips even in extreme ...As sea level rises,low-lying coastal cites face increasing threat of flood disruption,particularly in terms of human mobility.Commuters are vulnerable to bad weather,as it is difficult to cancel trips even in extreme weather conditions.Using Shanghai's automobile commuting population as an example,we categorized commuters by travel distance and income level to assess disruptions and delays due to floods,considering future sea level rise.The results show that local flooding disrupts commuting patterns by affecting roadways,with disruption decreasing with distance from the flooded area.This offers a mobility perspective on the indirect impacts of floods.During baseline flood events,long-distance commuters and the lowincome group are most affected,while short-distance commuters and the high-income group are less impacted.As sea level rises,floods will threaten all commuting groups,especially the high-income group.Using inaccessibility-commuting delay bivariate maps,this study revealed how socioeconomic differences impact mobility recovery after floods under climate change.The research highlights the differential impacts of floods on various socioeconomic groups in the context of climate change,offering insights for future urban planning and disaster mitigation strategies.展开更多
基金the financial support from the School of Applied Mathematics(FGV EMAp),and Fundacao Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro(FAPERJ)for the funding through process E-26/203.223/2017the financial support of CNPq(Brazil)through process 310452/2019-8.
文摘This study presents a mathematical model for optimal vaccination strategies in interconnected metropolitan areas,considering commuting patterns.It is a compartmental model with a vaccination rate for each city,acting as a control function.The commuting patterns are incorporated through a weighted adjacency matrix and a parameter that selects day and night periods.The optimal control problem is formulated to minimize a functional cost that balances the number of hospitalizations and vaccines,including restrictions of a weekly availability cap and an application capacity of vaccines per unit of time.The key findings of this work are bounds for the basic reproduction number,particularly in the case of a metropolitan area,and the study of the optimal control problem.Theoretical analysis and numerical simulations provide insights into disease dynamics and the effectiveness of control measures.The research highlights the importance of prioritizing vaccination in the capital to better control the disease spread,as we depicted in our numerical simulations.This model serves as a tool to improve resource allocation in epidemic control across metropolitan regions.
基金supported by the National Natural Science Foundation of China(Grant No.42371088)the China National Key R&D Program(Grant No.2023YFF0807000)the China Postdoctoral Science Foundation(Grant No.2024M763185)。
文摘As sea level rises,low-lying coastal cites face increasing threat of flood disruption,particularly in terms of human mobility.Commuters are vulnerable to bad weather,as it is difficult to cancel trips even in extreme weather conditions.Using Shanghai's automobile commuting population as an example,we categorized commuters by travel distance and income level to assess disruptions and delays due to floods,considering future sea level rise.The results show that local flooding disrupts commuting patterns by affecting roadways,with disruption decreasing with distance from the flooded area.This offers a mobility perspective on the indirect impacts of floods.During baseline flood events,long-distance commuters and the lowincome group are most affected,while short-distance commuters and the high-income group are less impacted.As sea level rises,floods will threaten all commuting groups,especially the high-income group.Using inaccessibility-commuting delay bivariate maps,this study revealed how socioeconomic differences impact mobility recovery after floods under climate change.The research highlights the differential impacts of floods on various socioeconomic groups in the context of climate change,offering insights for future urban planning and disaster mitigation strategies.
