For automated vehicles,comfortable driving will improve passengers’ satisfaction.Reducing fuel consumption brings economic profits for car owners,decreases the impact on the environment and increases energy sustainab...For automated vehicles,comfortable driving will improve passengers’ satisfaction.Reducing fuel consumption brings economic profits for car owners,decreases the impact on the environment and increases energy sustainability.In addition to comfort and fuel-economy,automated vehicles also have the basic requirements of safety and car-following.For this purpose,an adaptive cruise control (ACC) algorithm with multi-objectives is proposed based on a model predictive control (MPC) framework.In the proposed ACC algorithm,safety is guaranteed by constraining the inter-distance within a safe range; the requirements of comfort and car-following are considered to be the performance criteria and some optimal reference trajectories are introduced to increase fuel-economy.The performances of the proposed ACC algorithm are simulated and analyzed in five representative traffic scenarios and multiple experiments.The results show that not only are safety and car-following objectives satisfied,but also driving comfort and fuel-economy are improved significantly.展开更多
预测电动汽车充电需求的动态时空分布对于电网应对大规模电动汽车的接入具有重要意义。已有的研究缺乏能够同时精确描述电动汽车行驶过程中地理位置与荷电状态(state of charge,SOC)变化的数学模型。为了模拟电动汽车交通需求和充电需...预测电动汽车充电需求的动态时空分布对于电网应对大规模电动汽车的接入具有重要意义。已有的研究缺乏能够同时精确描述电动汽车行驶过程中地理位置与荷电状态(state of charge,SOC)变化的数学模型。为了模拟电动汽车交通需求和充电需求的动态时空变化过程,从电网调度的实际需求出发,改进了交通流领域中的微观交通仿真模型,结合Cruise软件计算的不同场景下的电动汽车每公里耗电量,提出了基于Agent-元胞自动机的电动汽车充电需求动态时空分布动态演化模型。最后,以54节点配电系统和25节点交通网络的耦合系统为例,说明所提方法可以预测快充站的电动汽车充电负荷,为电动汽车的充电负荷引导提供重要依据。展开更多
Connected automated vehicles(CAVs)serve as a promising enabler for future intelligent transportation systems because of their capabilities in improving traffic efficiency and driving safety,and reducing fuel consumpti...Connected automated vehicles(CAVs)serve as a promising enabler for future intelligent transportation systems because of their capabilities in improving traffic efficiency and driving safety,and reducing fuel consumption and vehicle emissions.A fundamental issue in CAVs is platooning control that empowers a convoy of CAVs to be cooperatively maneuvered with desired longitudinal spacings and identical velocities on roads.This paper addresses the issue of resilient and safe platooning control of CAVs subject to intermittent denial-of-service(DoS)attacks that disrupt vehicle-to-vehicle communications.First,a heterogeneous and uncertain vehicle longitudinal dynamic model is presented to accommodate a variety of uncertainties,including diverse vehicle masses and engine inertial delays,unknown and nonlinear resistance forces,and a dynamic platoon leader.Then,a resilient and safe distributed longitudinal platooning control law is constructed with an aim to preserve simultaneous individual vehicle stability,attack resilience,platoon safety and scalability.Furthermore,a numerically efficient offline design algorithm for determining the desired platoon control law is developed,under which the platoon resilience against DoS attacks can be maximized but the anticipated stability,safety and scalability requirements remain preserved.Finally,extensive numerical experiments are provided to substantiate the efficacy of the proposed platooning method.展开更多
An outbreak of COVID-19 developed aboard the Princess Cruises Ship during January eFebruary 2020.Using mathematical modeling and time-series incidence data describing the trajectory of the outbreak among passengers an...An outbreak of COVID-19 developed aboard the Princess Cruises Ship during January eFebruary 2020.Using mathematical modeling and time-series incidence data describing the trajectory of the outbreak among passengers and crew members,we characterize how the transmission potential varied over the course of the outbreak.Our estimate of the mean reproduction number in the confined setting reached values as high as^11,which is higher than mean estimates reported from community-level transmission dynamics in China and Singapore(approximate range:1.1e7).Our findings suggest that Rt decreased substantially compared to values during the early phase after the Japanese government implemented an enhanced quarantine control.Most recent estimates of Rt reached values largely below the epidemic threshold,indicating that a secondary outbreak of the novel coronavirus was unlikely to occur aboard the Diamond Princess Ship.展开更多
基金Project supported by the National Hi-Tech Research and Develop-ment Program (863) of China (No. 2006AA11Z204)the Qianji-ang Program of Zhejiang Province (No. 2009R10008)
文摘For automated vehicles,comfortable driving will improve passengers’ satisfaction.Reducing fuel consumption brings economic profits for car owners,decreases the impact on the environment and increases energy sustainability.In addition to comfort and fuel-economy,automated vehicles also have the basic requirements of safety and car-following.For this purpose,an adaptive cruise control (ACC) algorithm with multi-objectives is proposed based on a model predictive control (MPC) framework.In the proposed ACC algorithm,safety is guaranteed by constraining the inter-distance within a safe range; the requirements of comfort and car-following are considered to be the performance criteria and some optimal reference trajectories are introduced to increase fuel-economy.The performances of the proposed ACC algorithm are simulated and analyzed in five representative traffic scenarios and multiple experiments.The results show that not only are safety and car-following objectives satisfied,but also driving comfort and fuel-economy are improved significantly.
文摘预测电动汽车充电需求的动态时空分布对于电网应对大规模电动汽车的接入具有重要意义。已有的研究缺乏能够同时精确描述电动汽车行驶过程中地理位置与荷电状态(state of charge,SOC)变化的数学模型。为了模拟电动汽车交通需求和充电需求的动态时空变化过程,从电网调度的实际需求出发,改进了交通流领域中的微观交通仿真模型,结合Cruise软件计算的不同场景下的电动汽车每公里耗电量,提出了基于Agent-元胞自动机的电动汽车充电需求动态时空分布动态演化模型。最后,以54节点配电系统和25节点交通网络的耦合系统为例,说明所提方法可以预测快充站的电动汽车充电负荷,为电动汽车的充电负荷引导提供重要依据。
基金supported in part by Australian Research Council Discovery Early Career Researcher Award(DE210100273)。
文摘Connected automated vehicles(CAVs)serve as a promising enabler for future intelligent transportation systems because of their capabilities in improving traffic efficiency and driving safety,and reducing fuel consumption and vehicle emissions.A fundamental issue in CAVs is platooning control that empowers a convoy of CAVs to be cooperatively maneuvered with desired longitudinal spacings and identical velocities on roads.This paper addresses the issue of resilient and safe platooning control of CAVs subject to intermittent denial-of-service(DoS)attacks that disrupt vehicle-to-vehicle communications.First,a heterogeneous and uncertain vehicle longitudinal dynamic model is presented to accommodate a variety of uncertainties,including diverse vehicle masses and engine inertial delays,unknown and nonlinear resistance forces,and a dynamic platoon leader.Then,a resilient and safe distributed longitudinal platooning control law is constructed with an aim to preserve simultaneous individual vehicle stability,attack resilience,platoon safety and scalability.Furthermore,a numerically efficient offline design algorithm for determining the desired platoon control law is developed,under which the platoon resilience against DoS attacks can be maximized but the anticipated stability,safety and scalability requirements remain preserved.Finally,extensive numerical experiments are provided to substantiate the efficacy of the proposed platooning method.
文摘An outbreak of COVID-19 developed aboard the Princess Cruises Ship during January eFebruary 2020.Using mathematical modeling and time-series incidence data describing the trajectory of the outbreak among passengers and crew members,we characterize how the transmission potential varied over the course of the outbreak.Our estimate of the mean reproduction number in the confined setting reached values as high as^11,which is higher than mean estimates reported from community-level transmission dynamics in China and Singapore(approximate range:1.1e7).Our findings suggest that Rt decreased substantially compared to values during the early phase after the Japanese government implemented an enhanced quarantine control.Most recent estimates of Rt reached values largely below the epidemic threshold,indicating that a secondary outbreak of the novel coronavirus was unlikely to occur aboard the Diamond Princess Ship.
