To deal with the dynamic and imbalanced traffic requirements in Low Earth Orbit satellite networks, several distributed load balancing routing schemes have been proposed. However, because of the lack of global view, t...To deal with the dynamic and imbalanced traffic requirements in Low Earth Orbit satellite networks, several distributed load balancing routing schemes have been proposed. However, because of the lack of global view, these schemes may lead to cascading congestion in regions with high volume of traffic. To solve this problem, a Hybrid-Traffic-Detour based Load Balancing Routing(HLBR) scheme is proposed, where a Long-Distance Traffic Detour(LTD) method is devised and coordinates with distributed traffic detour method to perform self-adaptive load balancing. The forwarding path of LTD is acquired by the Circuitous Multipath Calculation(CMC) based on prior geographical information, and activated by the LTDShift-Trigger(LST) through real-time congestion perception. Simulation results show that the HLBR can mitigate cascading congestion and achieve efficient traffic distribution.展开更多
Background: The outbreak and global pandemic of coronavirus disease 2019 (COVID-19) attracts a great deal ofattentions to the problem of travel health. Cruise tourism is increasingly popular, with an estimated 30 mill...Background: The outbreak and global pandemic of coronavirus disease 2019 (COVID-19) attracts a great deal ofattentions to the problem of travel health. Cruise tourism is increasingly popular, with an estimated 30 millionpassengers transported on cruise ships worldwide each year. Safeguarding the health of cruise travelers duringthe entire travel is of ultimate importance for both the industry and global public health.Objective: This study aimed to explore the challenges and opportunities in travel health from the perspective ofglobal health governance.Methods: The global governance framework including problems, values, tools or regulations, and actors relatedto travel health were used to analyze the issues involved.Results: Up to April 2020, nearly thirty cruise ship voyages reported COVID-19 cases. The Diamond Princess,Grand Princess and Ruby Princess cruise ship had over 1,400 total reported COVID-19 cases, and more than 30deaths. A community with a common future in travel health is the core value of global health governance fortravel health. The travel-related international regulations, including the International Health Regulation (IHR[2005]), United Nations Convention on the Law of the Sea (UNCLOS) and the International Maritime Organization(IMO) conventions should be further updated to deal with the travel health problems. The roles andresponsibilities and the cooperation mechanisms of different actors are not clear in relation to the public healthemergencies during the travel.Conclusion: Travel health transcends national borders and involves multilevel actors, thus needs globalcooperation and governance. Regulations and legislation at global and country level are required to preventlarge-scale humanitarian crisis on travel health. Multilateral coordination, cooperation and collaborationmechanisms between governments, intergovernmental organizations, non-governmental organizations andindustry are needed to build a better community of common destiny for travel health.展开更多
基金supported by the National Science Foundation of China(No.61472189)Zhejiang Provincial Natural Science Foundation of China(No.LY18F030015)Wenzhou Public Welfare Science and Technology Project of China(No.G20150015)
文摘To deal with the dynamic and imbalanced traffic requirements in Low Earth Orbit satellite networks, several distributed load balancing routing schemes have been proposed. However, because of the lack of global view, these schemes may lead to cascading congestion in regions with high volume of traffic. To solve this problem, a Hybrid-Traffic-Detour based Load Balancing Routing(HLBR) scheme is proposed, where a Long-Distance Traffic Detour(LTD) method is devised and coordinates with distributed traffic detour method to perform self-adaptive load balancing. The forwarding path of LTD is acquired by the Circuitous Multipath Calculation(CMC) based on prior geographical information, and activated by the LTDShift-Trigger(LST) through real-time congestion perception. Simulation results show that the HLBR can mitigate cascading congestion and achieve efficient traffic distribution.
基金supported by the National Natural Science Foundationof China (No. 72042014).
文摘Background: The outbreak and global pandemic of coronavirus disease 2019 (COVID-19) attracts a great deal ofattentions to the problem of travel health. Cruise tourism is increasingly popular, with an estimated 30 millionpassengers transported on cruise ships worldwide each year. Safeguarding the health of cruise travelers duringthe entire travel is of ultimate importance for both the industry and global public health.Objective: This study aimed to explore the challenges and opportunities in travel health from the perspective ofglobal health governance.Methods: The global governance framework including problems, values, tools or regulations, and actors relatedto travel health were used to analyze the issues involved.Results: Up to April 2020, nearly thirty cruise ship voyages reported COVID-19 cases. The Diamond Princess,Grand Princess and Ruby Princess cruise ship had over 1,400 total reported COVID-19 cases, and more than 30deaths. A community with a common future in travel health is the core value of global health governance fortravel health. The travel-related international regulations, including the International Health Regulation (IHR[2005]), United Nations Convention on the Law of the Sea (UNCLOS) and the International Maritime Organization(IMO) conventions should be further updated to deal with the travel health problems. The roles andresponsibilities and the cooperation mechanisms of different actors are not clear in relation to the public healthemergencies during the travel.Conclusion: Travel health transcends national borders and involves multilevel actors, thus needs globalcooperation and governance. Regulations and legislation at global and country level are required to preventlarge-scale humanitarian crisis on travel health. Multilateral coordination, cooperation and collaborationmechanisms between governments, intergovernmental organizations, non-governmental organizations andindustry are needed to build a better community of common destiny for travel health.