On analyzing the achievement of the goal in the modern urban road traffic development planning,the alternative of Strategic Environmental Assessment for urban traffic planning should include the basic scheme,the exten...On analyzing the achievement of the goal in the modern urban road traffic development planning,the alternative of Strategic Environmental Assessment for urban traffic planning should include the basic scheme,the extended scheme and the environmental protection scheme. This study from different perspectives designed the alternatives for Changchun's county-level road and urban road system planning,and used the method of System Dynamics to simulate,optimize and analyze those alternatives. Thereafter,some methods including the correlation function method were used to comprehensively assess and rank those alternatives for recommending two best alternatives with the consideration to the indicators,such as the total emission amount of CO,the total emission amount of nitrogen oxides,the noise value,the road construction cost,the fossil oil consumption and the traffic capacity. The result showed that the study would provide substantial supports for decision-makers to make more scientific decisions and promote the sustainable urban traffic in Changchun City.展开更多
Environmental stress model is proposed as an effective tool to the analysis and evaluation of navigational safety in ports and waterways. Marine traffic simulations are carried out in a virtual port area with various ...Environmental stress model is proposed as an effective tool to the analysis and evaluation of navigational safety in ports and waterways. Marine traffic simulations are carried out in a virtual port area with various arrangements and conditions. Calculations of stress values and traffic volume criteria are illustrated. The simulation results provide a valuable hint for safety management of vessel traffic. The model provides quantitative information and helps administrators in decision making to achieve desired safety level and improve the efficiency of vessel traffic in ports and waterways.展开更多
绿色出行引导效果受外部信息及出行者选择偏好影响,需要考虑出行者潜在属性类别的异质性。自我呈现表现为人们通过控制与自己有关的信息来影响他人对自己的印象,体现了信息与选择偏好的交互作用。为定量分析出行者自我呈现意识和环保意...绿色出行引导效果受外部信息及出行者选择偏好影响,需要考虑出行者潜在属性类别的异质性。自我呈现表现为人们通过控制与自己有关的信息来影响他人对自己的印象,体现了信息与选择偏好的交互作用。为定量分析出行者自我呈现意识和环保意识对出行方式选择行为的影响,本文通过问卷调查收集到1382份有效样本,利用潜在类别模型(Latent Class Model,LCM)将出行者划分为高自我呈现组(18.23%)、中自我呈现组(20.26%)和低自我呈现组(61.51%)。离散选择模型的结果表明,出行者在进行方式选择时更关注出行时间和出行方式自身的特性,若不考虑方式特性,会高估出行费用对高自我呈现组的影响。高自我呈现组仅在短距离出行中对公共交通有强烈偏好,对于6~10 km的出行,选择私家车倾向明显。中短距离的出行中,低自我呈现组对骑行的偏好价值可以在一定程度上抵消过长出行时间带来的负效用。构建考虑出行者异质性的方式选择模型,可为政府和相关部门制定更协调、有针对性的交通调控政策及公共交通运营策略提供理论依据。展开更多
汽车直接横摆力矩控制(direct yaw moment control,DYC)系统用于有效避免车辆遇到非预计危险时的侧向运动,以保证汽车运行的稳定性和驾驶的安全性。目前,DYC系统大多采用分层结构。文章首先从车辆状态估计与环境感知、直接横摆力矩控制...汽车直接横摆力矩控制(direct yaw moment control,DYC)系统用于有效避免车辆遇到非预计危险时的侧向运动,以保证汽车运行的稳定性和驾驶的安全性。目前,DYC系统大多采用分层结构。文章首先从车辆状态估计与环境感知、直接横摆力矩控制器设计和力矩分配法这3个角度分析了汽车DYC系统架构,接着重点阐述了其对车速、车间距离、路面信息、横摆角速率以及车辆质心侧偏角等状态信息的获取与处理方法;然后介绍了上层控制器中车辆动力学参考模型、控制结构及不同变量控制的设计方法以及下层控制器中车辆横摆力矩的分配方式;最后总结了汽车直接横摆力矩控制系统现存的问题以及将来发展的方向。展开更多
基金Under the auspices of Major State Basic Research Development Program of China (973 Program) (No. 2005CB724205)Science Foundation Programme for Young Teachers of Northeast Normal University (No. 20070503)
文摘On analyzing the achievement of the goal in the modern urban road traffic development planning,the alternative of Strategic Environmental Assessment for urban traffic planning should include the basic scheme,the extended scheme and the environmental protection scheme. This study from different perspectives designed the alternatives for Changchun's county-level road and urban road system planning,and used the method of System Dynamics to simulate,optimize and analyze those alternatives. Thereafter,some methods including the correlation function method were used to comprehensively assess and rank those alternatives for recommending two best alternatives with the consideration to the indicators,such as the total emission amount of CO,the total emission amount of nitrogen oxides,the noise value,the road construction cost,the fossil oil consumption and the traffic capacity. The result showed that the study would provide substantial supports for decision-makers to make more scientific decisions and promote the sustainable urban traffic in Changchun City.
文摘Environmental stress model is proposed as an effective tool to the analysis and evaluation of navigational safety in ports and waterways. Marine traffic simulations are carried out in a virtual port area with various arrangements and conditions. Calculations of stress values and traffic volume criteria are illustrated. The simulation results provide a valuable hint for safety management of vessel traffic. The model provides quantitative information and helps administrators in decision making to achieve desired safety level and improve the efficiency of vessel traffic in ports and waterways.
文摘绿色出行引导效果受外部信息及出行者选择偏好影响,需要考虑出行者潜在属性类别的异质性。自我呈现表现为人们通过控制与自己有关的信息来影响他人对自己的印象,体现了信息与选择偏好的交互作用。为定量分析出行者自我呈现意识和环保意识对出行方式选择行为的影响,本文通过问卷调查收集到1382份有效样本,利用潜在类别模型(Latent Class Model,LCM)将出行者划分为高自我呈现组(18.23%)、中自我呈现组(20.26%)和低自我呈现组(61.51%)。离散选择模型的结果表明,出行者在进行方式选择时更关注出行时间和出行方式自身的特性,若不考虑方式特性,会高估出行费用对高自我呈现组的影响。高自我呈现组仅在短距离出行中对公共交通有强烈偏好,对于6~10 km的出行,选择私家车倾向明显。中短距离的出行中,低自我呈现组对骑行的偏好价值可以在一定程度上抵消过长出行时间带来的负效用。构建考虑出行者异质性的方式选择模型,可为政府和相关部门制定更协调、有针对性的交通调控政策及公共交通运营策略提供理论依据。
文摘汽车直接横摆力矩控制(direct yaw moment control,DYC)系统用于有效避免车辆遇到非预计危险时的侧向运动,以保证汽车运行的稳定性和驾驶的安全性。目前,DYC系统大多采用分层结构。文章首先从车辆状态估计与环境感知、直接横摆力矩控制器设计和力矩分配法这3个角度分析了汽车DYC系统架构,接着重点阐述了其对车速、车间距离、路面信息、横摆角速率以及车辆质心侧偏角等状态信息的获取与处理方法;然后介绍了上层控制器中车辆动力学参考模型、控制结构及不同变量控制的设计方法以及下层控制器中车辆横摆力矩的分配方式;最后总结了汽车直接横摆力矩控制系统现存的问题以及将来发展的方向。