融合卡尔曼滤波的高速公路状态估计误差界限分析

为分析高速公路交通流检测数据质量,本文构建平方流量误差界(Squared Flow Error Bound, SFEB)和扩展卡尔曼滤波(Extended Kalman Filter, EKF)的决策级融合模型SFEB-EKF,在检测器空间覆盖不足情况下,计算检测路段和无检测器路段的交通状态估计误差界限。与SFEB 算法相比,融合模型利用EKF交通状态估计模型估计全路段交通状态,基于得到的估计样本计算全路段交通状态估计误差下界。同时,采用最近邻法(Nearest Neighbor Method, NNM)计算全路段交通状态估计误差上界。应用开源高速公路数据集测试模型,结果表明,与需要输入真实样本的SFEB算法相比,融合模型SFEB-EKF在缺少真实样本情况下,能取得相似的结果且误差保持 在5%以内,不同检测器覆盖率实验下模型表现出良好的稳定性。本文模型通过给出无检测器路段交通状态估计界限,为高速公路交通检测器布设方案提供参考。     

大水位差港口客运缆车控制系统方案设计

针对大水位差港口的水文特征和地理特征 ,提出了其客运缆车控制系统的技术方案。该方案运用先进的控制技术和网络通信技术 ,大大加强了对缆车的运行管理和监控力度 ,提高了安全性和可靠性     

基于“互联网+”的智慧交通顶层设计架构

基于国家“互联网+”及交通运输部提出的“四个交通”发展战略的指导,通过对国内外智慧交通发展现状进行研究分析,针对智慧交通顶层架构进行深入研究,提出可持续发展的智慧交通总体架构建设思路,阐述1+4+NX的总体架构建设内容,明确各应用系统的架构层级及相互关系,并在此基础上,在北京、西安、西宁等城市智慧交通建设项目中进行实际应用,为城市智慧交通建设发展提供顶层建设依据。     

��·Эͬ�µ�·������źſ����Ż�����

车路协同系统能实时获取车辆个体的运行状态信息,并能通过速度引导实现车辆与交通控制系统之间的动态交互,为交通信号控制提供了新的数据源和技术手段.分析了现有车路协同下交通信号控制方法存在的不足,引入基于时间窗的滚动预测方法,提出了改进的交叉口信号控制优化流程;将相位饱和度作为表征信号控制效果的指标,在考虑速度引导对车辆运行状态影响基础上,建立了车路协同环境下道路交叉口信号控制优化方法和模型.运用VISSIM软件进行了仿真实验,结果表明,本文方法优于感应控制方法,在各种交通流量下均能有效降低交叉口平均延误和停车次数.     

智慧交通与智慧物流

智慧交通和智慧物流是智慧城市建设的重要内容.智慧交通技术的创新和发展，促进了智能交通升级.解决大规模数据计算问题是物流智能化的基础.本次论坛以“智慧交通和智慧物流”为主题，介绍了安全驾驶统一集理论、实践及成果，探讨了新一代信息技术对智能交通发展与创新的推动作用，介绍了无人驾驶技术的总体框架、发展与应用，探讨了智慧物流所面临的大规模数据计算问题及解决方案.     

“9·11”事件前后美国轨道交通的安全情况

2001年发生的"9·11"事件,不可逆转地改变了美国人对安全准备工作的内涵与认识。虽然新安保措施的着重点主要放在航空运输方面,但人们也更加注重陆地公共交通系统的安全形势,因为公众关注的焦点从"9·11"之前的私人财产犯罪转变为恐怖主义活动。然而,美国的铁路运营安全却被现实的情况所限制:当前紧缩的财政预算无法构建一个巨大的、均匀分级的保安网络。上述的两种形势相互作用,促使有关部门在"9·11"之后采取更为合理和实际的铁路安全措施,并由此催生了一些新方法来解决在根基上原本就脆弱的网络体系问题。交通安全部门和民间研究小组的结论是:对所有公共交通基础设施提供一整套安全设施是不必要的。     

公路运梁对铺架施工影响及对策探析

公路运输铁路T梁施工在近年的铁路建设项目上时有出现,运梁方式的改变对于铺轨架梁施工有较大影响。从运梁设备的选型、加固方式及喂梁方式的变化和上砟方式变化等方面进行探讨分析,以期对类似施工项目有所借鉴。     

A fundamental investigation of tilt control systems for narrow commuter vehicles

One way of addressing traffic congestion is by efficiently utilizing the existing highway infrastructure. Narrow tilting vehicles that need a reduced width lane can be part of the solution if they can be designed to be safe, stable, and easy to operate. In this paper, a control system that stabilizes the tilt mode of such a vehicle without affecting the handling of the vehicle is proposed. This control system is a combination of two different types of control schemes known as steering tilt control (STC) and direct tilt control (DTC) systems. First, different existing variations of both STC and DTC systems are considered and their shortcomings analysed. Modified control schemes are then suggested to overcome the deficiencies. Then a new method of integrating these two control schemes that guarantees smooth switchover between the controllers as a function of vehicle velocity is proposed. The performance of the proposed STC, DTC, and integrated systems is evaluated by carrying out simulations for different operating conditions and some experimental work. The design of a second-generation narrow tilting vehicle on which the developed control system has been implemented is presented.     

基于路网可达性的城市交通离散网络设计模型及算法

根据城市交通路网分区理论,把分成的子区看成一个节点,考虑所有节点的可达性,以此度量整个路网的可达性,设计了基于路网可达性最大为目标的城市交通离散网络设计模型。采用粒子群算法,并给出一个简单的算例,算例表明,合理的添加路段,能使城市路网可达性达到最大。     

Camera calibration and vehicle tracking: Highway traffic video analytics

We describe a real-time highway surveillance system (RHSS), which operates autonomously to collect statistics (speed and volume) and generates incident alerts (e.g., stopped vehicles). The system is designed to optimize long-term real-time performance accuracy. It also provides convenient integration to an existing surveillance infrastructure with different levels of service. Innovations include a novel 3-D Hungarian algorithm which is utilized for object tracking and a practical, hands-off mechanism for camera calibration. Speed is estimated based on trajectories after mapping/alignment with respect to dominant paths learned based on an evolutionary dynamics model. The system, RHSS, is intensively evaluated under different scenarios such as rain, low-contrast and high-contrast lightings. Performance is presented in comparison to a current commercial product. The contribution is innovation of new technologies that enable hands-off calibration (i.e., automatic detection of vanishing points) and improved accuracy (i.e., illumination balancing, tracking via a new 3-D Hungarian algorithm, and re-initialization of background detection on-the-fly). Results indicate the capability and applicability of the proposed system in real-time and real-world settings.