新型有轨电车信号系统方案研究

新型有轨电车是未来城市轨道交通发展的重要方向。信号系统是有轨电车的重要组成部分,保障列车的安全和运营的效率。介绍了新型有轨电车的特点,分析了新型有轨电车的行车安全控制方案。通过计算和数据分析,认为针对新型有轨电车高效、廉价等特点,其信号系统采用站间闭塞行车间隔控制方案较为合理。     

城市轨道交通无人驾驶的关键技术特点分析

介绍了无人驾驶技术的定义,阐述了运营驾驶所有环节全面自动化、减少信号系统后备模式和转移列车司机职能,以及无人驾驶技术的核心理念等。还从各类接口、停车场设计、全方位视频监控及分析、通信系统等介绍了无人驾驶的关键技术,并提出无人驾驶的难点和挑战。     

城市轨道交通网络化运营组织技术研究评述

本文阐述了城市轨道交通网络化运营的概念,分析了网络化运营的物理环境及其客流基本特征,提出了城市轨道交通公益性的3个重要标志.通过对国内外城市轨道交通网络化运营理论与实践的评述,提出了城市轨道交通网络化运营的主要目标;指出了网络化运营管理面临的三大主要问题,即断面负荷均衡、车站负荷均衡及换乘衔接改善.基于既有的多交路、多编组、快慢车及过轨运营等主要网络化运营技术,分析不同方法的技术特点及其对出行者的影响,提出了不同方法的适用性.最后,从不同角度分析了不同网络化运营技术实施过程对乘客与企业的具体效果,提出了促进我国城市轨道交通网络化技术应用的建议.     

可扩展的高精度磁场采集系统的设计

当对弱磁场进行测量时,对磁场采集系统的性能提出了更高的要求,设计了一种基于Σ-Δ技术模数转换器的高精度数据采集系统,并对测磁系统进行了多通道扩展。通过硬件和软件优化相结合的方式提高系统的测量精度,硬件优化包括抗混频滤波和消除供电电源带来的干扰,软件优化包括对采样数据进行FIR低通滤波、标度变换和平滑滤波。实验证明,设计的磁场采集系统精度良好,满足了项目中对于系统扩展和精度的要求。     

A bi-level model of dynamic traffic signal control with continuum approximation

This paper proposes a bi-level model for traffic network signal control, which is formulated as a dynamic Stackelberg game and solved as a mathematical program with equilibrium constraints (MPEC). The lower-level problem is a dynamic user equilibrium (DUE) with embedded dynamic network loading (DNL) sub-problem based on the LWR model (Lighthill and Whitham, 1955; Richards, 1956). The upper-level decision variables are (time-varying) signal green splits with the objective of minimizing network-wide travel cost. Unlike most existing literature which mainly use an on-and-off (binary) representation of the signal controls, we employ a continuum signal model recently proposed and analyzed in Han et al. (2014), which aims at describing and predicting the aggregate behavior that exists at signalized intersections without relying on distinct signal phases. Advantages of this continuum signal model include fewer integer variables, less restrictive constraints on the time steps, and higher decision resolution. It simplifies the modeling representation of large-scale urban traffic networks with the benefit of improved computational efficiency in simulation or optimization. We present, for the LWR-based DNL model that explicitly captures vehicle spillback, an in-depth study on the implementation of the continuum signal model, as its approximation accuracy depends on a number of factors and may deteriorate greatly under certain conditions. The proposed MPEC is solved on two test networks with three metaheuristic methods. Parallel computing is employed to significantly accelerate the solution procedure.     

道路交通组织方案综合服务水平评价分析研究

为了缓解城市道路平面信号交叉口的交通拥堵问题,提出利用渠化及冲突点法对交叉口进行组织优化,并应用synchro仿真软件获取信号交叉口的各项控制指标,采用层次分析法对交叉口的交通服务水平进行综合评价。通过对呼和浩特火车站交叉口优化前后的交通服务水平评价对比,得出该方案对提高城市道路平面信号交叉口的交通运行效率,改善交通运行环境具有实用性。     

客运专线地面信号设置与CTCS-2级后备模式探讨

阐述了客运专线铁路设置地面信号机和CTCS-2级后备模式的必要性和实用性。     

Mechanism Analysis and Implementation Framework for Traffic Signal Control of Over-saturated Intersection Group

For the purpose of improving traffic signal control at over-saturated intersection group, the traffic control targets and structure were optimized, and an implementation framework was proposed. After analyzing the congestion inducements, the maximum throughput and minimum average queue of critical route were selected as the optimization objectives. The critical route layer was added to optimize control structure. The implementation framework for signal timing plan optimization was also put forward considering the over-saturated traffic control characters. Detailed optimization measures for each layer were also discussed. Simulations with the traffic data of an intersection group at Guangzhou Road in Nanjing were selected to compare the performance of dynamic timing plan using proposed strategy and static timing plan. The results indicated the proposed method can be used to optimize traffic signal control of over-saturated intersections group with satisfying robustness and reliability.     

英版航海图书资料的新发展

随着计算机及互联网技术的发展,航海人员常用的航海图书资料的出版形式也有了很大的变化,掌握这些变化对有效快捷地使用航海资料是非常有帮助的。从这一点出发,对英版资料最新发展情况作一阐述。     

干线协调控制中公共周期优化方法研究

现有线控公共周期确定取决于关键交叉口交通状态，其目的是满足交通状态最差的交叉口不会产生过饱和现象，但未考虑对实际线控效果影响且可能增大其他交叉口延误。文章分析了周期调整对延误和通行能力产生的影响，确定了干线协调下公共周期的调整区间。在此区间内以交叉口实际间距与理想间距偏差为优化目标，采用优选出的鲁棒简面体爬山法优化目标函数实现绿波带最宽。实证表明所提出的优化方法得到的绿波带和平均延误好于数解法，且对通行能力影响很小。