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排序方式: 共有413条查询结果,搜索用时 31 毫秒
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考虑网联自动驾驶车辆(Connected Autonomous Vehicle, CAV)应用先进的车联网与自动驾驶技术,可以采用智能交叉口的组织形式,大幅提升交叉口的通行效率,为降低CAV与人工驾驶车辆(Human-driven Vehicle, HV)混行条件下城市交通系统的整体出行成本,提出智能交叉口在城
市交通网络中的布局优化问题,建立数学优化模型并求解。首先,基于对两类车辆行驶特性的分析,建立混合用户均衡模型,描述CAV与HV的路径选择行为;其次,从交通规划者的角度,以系统最优为目标,整合混合用户均衡模型,建立面向新型混合交通流的智能交叉口网络布局优化模型,并利用改进的遗传算法求解;最后,选取Sioux-Falls交通网络作为案例分析,验证模型与算法的有效性,并研究CAV渗透率变化对优化结果的影响。研究表明,智能交叉口在城市路网中的合理规划极大地提高了新型混行场景下城市交通系统的出行效率,同时,大幅降低了由于网联自动
驾驶单方面技术优势带来的CAV与HV的出行效率差距,增进了出行公平性。 相似文献
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ZHU Hai-tao ZHANG Xu ZHANG Jia-tai HU Sheng-haiCollege of Mechanical Electrical Engineering Harbin Engineering University Harbin China 《船舶与海洋工程学报》2002,1(2):62-65
In this paper, a smart crank and slider mechanism is analyzed mostly from a dynamic view. By means of dynamic explicit finite element method, 3D nonlinear structure is simulated. It is proved that the mechanism can effectively accomplish smart movement prescribed. And in order to ensure reciprocal movement with higher frequency, measures should be taken to avoid over heating of parts. Compared with internal energy, kinetic energy of total rigid body is dominating, and Y direction equivalent rigid velocity is much higher than X direction velocity. Equivalent rigid velocity of all parts is consistent with respective movement condition. For both energy and velocity, slider effect is dominating. Three direction equivalent inertia force oscillates. Force amplitude in Y -direction is comparitively the greatest. 相似文献
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本文结合某港散货港区智慧港口规划项目,介绍了该港南作业区智能化项目的核心在于构建一套适应现代散杂货港口发展趋势、突破传统散货港口作业模式的全新港口智能化系统。本次规划将物联网、大数据技术、AI人工智能、5G等新型基础设施与生产业务融合,创新生产作业流程及资源配置,显著提高港口的作业运营能力、物流协同能力、口岸支持能力、客户服务能力,助力某港打造全国领先的基于5G+数字中台+AI的智慧散货港区。 相似文献
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自动售检票(AFC)系统作为城市轨道交通中与乘客接触最为紧密的系统,应基于“以用户为中心”来提升客运服务水平。通过优化系统层级、整合多元化支付平台、引入智能客服功能、对接电子发票系统等措施,规划设计了适用于广州新一轮城市轨道交通线网建设要求的AFC系统架构,以期打造智慧的AFC系统,为乘客提供更为人性化和多元化的服务。 相似文献
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Smart card data are increasingly used for transit network planning, passengers’ behaviour analysis and network demand forecasting. Public transport origin–destination (O–D) estimation is a significant product of processing smart card data. In recent years, various O–D estimation methods using the trip-chaining approach have attracted much attention from both researchers and practitioners. However, the validity of these estimation methods has not been extensively investigated. This is mainly because these datasets usually lack data about passengers’ alighting, as passengers are often required to tap their smart cards only when boarding a public transport service. Thus, this paper has two main objectives. First, the paper reports on the implementation and validation of the existing O–D estimation method using the unique smart card dataset of the South-East Queensland public transport network which includes data on both boarding stops and alighting stops. Second, the paper improves the O–D estimation algorithm and empirically examines these improvements, relying on this unique dataset. The evaluation of the last destination assumption of the trip-chaining method shows a significant negative impact on the matching results of the differences between actual boarding/alighting times and the public transport schedules. The proposed changes to the algorithm improve the average distance between the actual and estimated alighting stops, as this distance is reduced from 806 m using the original algorithm to 530 m after applying the suggested improvements. 相似文献
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舰船操纵的灵活性和准确性在一定程度上取决于舵的性能,而对于潜艇而言,舵的作用更加重要。为了提高潜艇战斗力,目前各国都在争相研制新一代自动舵,期盼在控制航向的同时控制深度,从而提高水下生命力和战斗力。论文介绍了自动舵的发展历程,比较了各种控制方法的特点,最后提出了自己的一点见解。 相似文献
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Mobile ICTs and physical mobility: Review and research agenda 总被引:1,自引:0,他引:1
Anne Aguiléra Caroline Guillot 《Transportation Research Part A: Policy and Practice》2012,46(4):664-672
The question of the relationship between the spread of communication tools and the physical mobility of individuals is not new and arose with the arrival of the fixed telephone and, more recently, the development of the Internet and especially e-commerce. The extraordinary spread of individual, especially portable, communication tools like the mobile phone, has recently generated new interest in this topic in the fields of transportation economics, geography and sociology. This article discusses the main topics that have been explored, from the debate between complementarity and substitution to analyses in terms of interactions with the spatiotemporal organization of daily activities, the size and maintenance of social networks, and, finally, perception of travel and spaces. We then identify several issues that we think merit further exploration. 相似文献
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On July 1st, 2008, California enacted a ban on hand-held cell phone use while driving. Using California Highway Patrol panel accident data for California freeways from January 1st, 2008 to December 31st, 2008, we examine whether this policy reduced the number of accidents on California highways. To control for unobserved time-varying effects that could be correlated with the ban, we use high-frequency data and a regression discontinuity design. We find no evidence that the ban on hand-held cell phone use led to a reduction in traffic accidents. 相似文献