The post-earthquake emergency period,which is a sensitive time segment just after an event,mainly focuses on saving life and restoring social order.To improve the seismic resilience of city road networks,a resilience ...The post-earthquake emergency period,which is a sensitive time segment just after an event,mainly focuses on saving life and restoring social order.To improve the seismic resilience of city road networks,a resilience evaluation method used in the post-earthquake emergency period is proposed.The road seismic damage index of a city road network can consider the influence of roads,bridges and buildings along the roads,etc.on road capacity after an earthquake.A function index for a city road network is developed,which reflects the connectivity,redundancy,traffic demand and traffic function of the network.An optimization model for improving the road repair order in the post-earthquake emergency period is also developed according to the resilience evaluation,to enable decision support for city emergency management and achieve the best seismic resilience of the city road network.The optimization model is applied to a city road network and the results illustrate the feasibility of the resilience evaluation and optimization method for a city road network in the post-earthquake emergency period.展开更多
Objective:To determine the clinical and epidemiological features of pelvic fracture patients presenting to the Emergency Department.Methods:This prospective observational study was conducted in a tertiary care center ...Objective:To determine the clinical and epidemiological features of pelvic fracture patients presenting to the Emergency Department.Methods:This prospective observational study was conducted in a tertiary care center in south India.Causes of injury,types of pelvic fractures,the associated injuries,and outcome at the time of discharge were recorded.Results:A total of 140 patients were included in this study.Most patients were classified as type A(n=62),followed by type B(n=48)and type C(n=30).A total of 112 patients were injured due to road traffic accidents,followed by a fall from a height(n=23)and a fall from a heavy object(n=5).Most subjects had facial injuries(n=99,70.7%),followed by head injuries(n=51,36.4%).Five percent of the patients were expired,12%left against medical advice,and 83%were discharged.Conclusions:The incidence of pelvic fractures presenting to the Emergency Department is relatively high in India.Road traffic accidents are the primary cause of pelvic fractures and associated facial and head injuries.The outcomes demonstrate the need for improved prevention strategies and comprehensive management protocols to reduce mortality.展开更多
How to improve the rescue efficiency of the network after the earthquake is the key content of emergency management decision-making, improve the efficiency of emergency rescue, and reduce the impact of emergency rescu...How to improve the rescue efficiency of the network after the earthquake is the key content of emergency management decision-making, improve the efficiency of emergency rescue, and reduce the impact of emergency rescue to the non victims. Using cyberspace of lifeline network traffic and emergency transportation problem, considering the network restoration problem of disaster area, earthquake emergency supplies distribution model is established. In the model, to consider the need to repair the damaged sections and the existing emergency rescue generated traffic volume of emergency rescue network effects. And design heuristic algorithm for solving the model. Finally the example shows that in emergency rescue, emergency rescue of critical damage repair the road and traffic control of the whole lifeline network rescue efficiency highest, with the average nuisance greatly reduce, the lifeline network connectivity reliability.展开更多
To determine the dynamic influence range of emergencies under special events, the spacial and temporal characteristics of the traffic flow are studied by simulation based on the cell transmission model (CTM). Based ...To determine the dynamic influence range of emergencies under special events, the spacial and temporal characteristics of the traffic flow are studied by simulation based on the cell transmission model (CTM). Based on the traffic management measures used under special events, a semi-dynamic assignment algorithm is proposed, which is combined with an algorithm for logit multi-path traffic assignment and the CTM. In a simple calculation network, the spacial and temporal characteristics of traffic flows which vary with different traffic management schemes are studied, and a method to obtain the influence range of emergency is proposed by computing the jam time of the intersections. By contrasting the average delay of each vehicle, the dissipation effect is studied under two different traffic management schemes. The example shows that the spatial and temporal variety of the traffic flow can be easily simulated and the influence range of emergency can be confirmed by the method based on the CTM. The proposed method provides a new idea for decision-making on traffic management under emergency under special events.展开更多
Vehicular ad-hoc networks(VANETs)play an essential role in enhancing transport infrastructure by making vehicles intelligent and proficient in preventing traffic fatalities.Direction-based greedy protocols pick the ne...Vehicular ad-hoc networks(VANETs)play an essential role in enhancing transport infrastructure by making vehicles intelligent and proficient in preventing traffic fatalities.Direction-based greedy protocols pick the next route vehicle for transmitting emergency messages(EMs)depending upon the present location of adjacent vehicles towards sink vehicles by using an optimal uni-directional road traffic approach.Nevertheless,such protocols suffer performance degradation by ignoring the moving directions of vehicles in bi-directional road traffic where topological changes happen continuously.Due to the high number of vehicles,it is essential to broadcast EMs to all vehicles to prevent traffic delays and collisions.A cluster-based EM transmitting technique is proposed in this paper.For urban VANETs,this paper pioneers the clustering of bi-directional road traffic for robust and efficient routing of EMs.In this regard,this paper introduces a routing protocol,namely,the bi-directional urban routing protocol(BURP).In addition to the paths and relative locations of vehicles,BURP takes account of the distance parameter by using the Hamming distance function to determine the direction ofmotion of vehicles and communicates EMs through the cluster head(CH).Amodified k-medoids algorithm is presented for the clustering of bi-directional road traffic.A median method is presented for selecting CH to ensure the longrunning of a cluster.Simulation results show that BURP provides enhanced throughput,a maximized packet delivery ratio,low energy consumption,and network delay relative to eminent routing protocols.展开更多
近年来,极端天气事件发生频次不断增加,强度不断加大,其中,由暴雨引发的城市内涝导致交通应急事件发生概率进一步增大。为提升暴雨灾害下应急救援响应速度,本文开展应急车辆救援路径优化研究。以通行时间最短为目标,考虑路面积水对车辆...近年来,极端天气事件发生频次不断增加,强度不断加大,其中,由暴雨引发的城市内涝导致交通应急事件发生概率进一步增大。为提升暴雨灾害下应急救援响应速度,本文开展应急车辆救援路径优化研究。以通行时间最短为目标,考虑路面积水对车辆通行速度的动态影响,构建应急车辆救援路径优化模型,提出动态最短路径优化算法求解模型。选取上海市长宁区东北部作为研究区域,根据SWMM(Storm Water Management Model)模拟得到的50年一遇暴雨条件下城市道路路面的积水情况,设定应急救援场景,求解应急救援路径。通过本文提出算法求解得到的路径与传统静态最短路径算法求解结果对比可知,通行用时同比减少了25.42%。同时,考虑应急物资储备情况分配应急救援任务,扩展了算法的应用场景,形成可靠和高效的应急响应方案,可为提升暴雨灾害下应急响应效率提供参考。展开更多
为了减弱极端事件对综合能源系统的影响,尽早恢复各类负荷,提高系统弹性。文中提出了一种考虑交通网与配电网级别的区域电-气互联系统(Interconnection Electric and Gas System,IEGS)协同运行的灾后故障抢修策略。首先,通过元胞传输模...为了减弱极端事件对综合能源系统的影响,尽早恢复各类负荷,提高系统弹性。文中提出了一种考虑交通网与配电网级别的区域电-气互联系统(Interconnection Electric and Gas System,IEGS)协同运行的灾后故障抢修策略。首先,通过元胞传输模型建立了考虑系统实时恢复指标修正的交通流量分配模型,对交通网的交通流量进行预测;其次,在故障预分配的前提下建立了区域IEGS的故障恢复模型,协调优化维修队、分布式电源、配电网网架等资源,减少停电损失;然后以维修队的最小通行时间矩阵以及由系统实时恢复指标得到的交通网道路修正参数作为传递变量,在维修队开始移动的时间点,重新计算后续的修复计划以及交通网的运行情况,进行多时间断面优化;最后,通过算例仿真进行对比,验证了所提策略的有效性,并分析移动储能装置对故障恢复的影响。展开更多
基金National Natural Science Foundation of China under Grant Nos.U1939210 and 51825801。
文摘The post-earthquake emergency period,which is a sensitive time segment just after an event,mainly focuses on saving life and restoring social order.To improve the seismic resilience of city road networks,a resilience evaluation method used in the post-earthquake emergency period is proposed.The road seismic damage index of a city road network can consider the influence of roads,bridges and buildings along the roads,etc.on road capacity after an earthquake.A function index for a city road network is developed,which reflects the connectivity,redundancy,traffic demand and traffic function of the network.An optimization model for improving the road repair order in the post-earthquake emergency period is also developed according to the resilience evaluation,to enable decision support for city emergency management and achieve the best seismic resilience of the city road network.The optimization model is applied to a city road network and the results illustrate the feasibility of the resilience evaluation and optimization method for a city road network in the post-earthquake emergency period.
文摘Objective:To determine the clinical and epidemiological features of pelvic fracture patients presenting to the Emergency Department.Methods:This prospective observational study was conducted in a tertiary care center in south India.Causes of injury,types of pelvic fractures,the associated injuries,and outcome at the time of discharge were recorded.Results:A total of 140 patients were included in this study.Most patients were classified as type A(n=62),followed by type B(n=48)and type C(n=30).A total of 112 patients were injured due to road traffic accidents,followed by a fall from a height(n=23)and a fall from a heavy object(n=5).Most subjects had facial injuries(n=99,70.7%),followed by head injuries(n=51,36.4%).Five percent of the patients were expired,12%left against medical advice,and 83%were discharged.Conclusions:The incidence of pelvic fractures presenting to the Emergency Department is relatively high in India.Road traffic accidents are the primary cause of pelvic fractures and associated facial and head injuries.The outcomes demonstrate the need for improved prevention strategies and comprehensive management protocols to reduce mortality.
文摘How to improve the rescue efficiency of the network after the earthquake is the key content of emergency management decision-making, improve the efficiency of emergency rescue, and reduce the impact of emergency rescue to the non victims. Using cyberspace of lifeline network traffic and emergency transportation problem, considering the network restoration problem of disaster area, earthquake emergency supplies distribution model is established. In the model, to consider the need to repair the damaged sections and the existing emergency rescue generated traffic volume of emergency rescue network effects. And design heuristic algorithm for solving the model. Finally the example shows that in emergency rescue, emergency rescue of critical damage repair the road and traffic control of the whole lifeline network rescue efficiency highest, with the average nuisance greatly reduce, the lifeline network connectivity reliability.
基金The National High Technology Research and Development Program of China(863 Program)(No.2007AA11Z210)
文摘To determine the dynamic influence range of emergencies under special events, the spacial and temporal characteristics of the traffic flow are studied by simulation based on the cell transmission model (CTM). Based on the traffic management measures used under special events, a semi-dynamic assignment algorithm is proposed, which is combined with an algorithm for logit multi-path traffic assignment and the CTM. In a simple calculation network, the spacial and temporal characteristics of traffic flows which vary with different traffic management schemes are studied, and a method to obtain the influence range of emergency is proposed by computing the jam time of the intersections. By contrasting the average delay of each vehicle, the dissipation effect is studied under two different traffic management schemes. The example shows that the spatial and temporal variety of the traffic flow can be easily simulated and the influence range of emergency can be confirmed by the method based on the CTM. The proposed method provides a new idea for decision-making on traffic management under emergency under special events.
文摘Vehicular ad-hoc networks(VANETs)play an essential role in enhancing transport infrastructure by making vehicles intelligent and proficient in preventing traffic fatalities.Direction-based greedy protocols pick the next route vehicle for transmitting emergency messages(EMs)depending upon the present location of adjacent vehicles towards sink vehicles by using an optimal uni-directional road traffic approach.Nevertheless,such protocols suffer performance degradation by ignoring the moving directions of vehicles in bi-directional road traffic where topological changes happen continuously.Due to the high number of vehicles,it is essential to broadcast EMs to all vehicles to prevent traffic delays and collisions.A cluster-based EM transmitting technique is proposed in this paper.For urban VANETs,this paper pioneers the clustering of bi-directional road traffic for robust and efficient routing of EMs.In this regard,this paper introduces a routing protocol,namely,the bi-directional urban routing protocol(BURP).In addition to the paths and relative locations of vehicles,BURP takes account of the distance parameter by using the Hamming distance function to determine the direction ofmotion of vehicles and communicates EMs through the cluster head(CH).Amodified k-medoids algorithm is presented for the clustering of bi-directional road traffic.A median method is presented for selecting CH to ensure the longrunning of a cluster.Simulation results show that BURP provides enhanced throughput,a maximized packet delivery ratio,low energy consumption,and network delay relative to eminent routing protocols.
文摘近年来,极端天气事件发生频次不断增加,强度不断加大,其中,由暴雨引发的城市内涝导致交通应急事件发生概率进一步增大。为提升暴雨灾害下应急救援响应速度,本文开展应急车辆救援路径优化研究。以通行时间最短为目标,考虑路面积水对车辆通行速度的动态影响,构建应急车辆救援路径优化模型,提出动态最短路径优化算法求解模型。选取上海市长宁区东北部作为研究区域,根据SWMM(Storm Water Management Model)模拟得到的50年一遇暴雨条件下城市道路路面的积水情况,设定应急救援场景,求解应急救援路径。通过本文提出算法求解得到的路径与传统静态最短路径算法求解结果对比可知,通行用时同比减少了25.42%。同时,考虑应急物资储备情况分配应急救援任务,扩展了算法的应用场景,形成可靠和高效的应急响应方案,可为提升暴雨灾害下应急响应效率提供参考。
文摘为了减弱极端事件对综合能源系统的影响,尽早恢复各类负荷,提高系统弹性。文中提出了一种考虑交通网与配电网级别的区域电-气互联系统(Interconnection Electric and Gas System,IEGS)协同运行的灾后故障抢修策略。首先,通过元胞传输模型建立了考虑系统实时恢复指标修正的交通流量分配模型,对交通网的交通流量进行预测;其次,在故障预分配的前提下建立了区域IEGS的故障恢复模型,协调优化维修队、分布式电源、配电网网架等资源,减少停电损失;然后以维修队的最小通行时间矩阵以及由系统实时恢复指标得到的交通网道路修正参数作为传递变量,在维修队开始移动的时间点,重新计算后续的修复计划以及交通网的运行情况,进行多时间断面优化;最后,通过算例仿真进行对比,验证了所提策略的有效性,并分析移动储能装置对故障恢复的影响。