京津冀一体化轨道交通协调发展研究和展望

京津冀协同发展上升为国家战略,需要区域轨道交通协调发展来支撑和服务于区域一体化发展。从京津冀协同发展空间布局及产业转移的角度出发,提出各种轨道交通的层次及服务功能,在此基础上对轨道交通协调发展研究提出应抓住规划,处理好既有轨道交通与新增轨道交通、客货运主要通道与交通引导(TOD)、各种轨道交通间协调衔接等方面关系;加快投融资改革,实施同步建设;创新体制,实现管理协调发展;加大政策扶持,达到轨道交通可持续发展等方面进行研究,同时对区域轨道交通进行展望,对京津冀一体化轨道交通协调发展研究方向、研究领域和空间进行了浅议。     

阿拉山口口岸站货运安全问题的分析及对策

针对阿拉山口站货运作业中存在散堆装货物超载、成件小包装货物超载、集装箱偏载等问题,提出严格执行作业流程,约束和规范装载机械司机的操作行为,消除监控盲区,建立抽检制度、建立超偏载检测装置故障停用应急机制,建立装车前对货件标重检斤的制度,约束国外发货人的行为,保证货物装箱质量等保障货物运输安全的对策。     

Fuzzy-logic-based incident detection for signalized diamond interchanges

This paper documents a fuzzy-logic-based incident detection algorithm for signalized urban diamond interchanges. The model is capable of detecting lane-blocking incidents whose effects are manifested by patterns of deterioration in traffic conditions that require adjustments in signal control strategies. As a component of a real-time traffic adaptive control system for signalized diamond interchanges, the algorithm feeds an incident report (i.e., the time, location, and severity of the incident) to the system's optimization manager, which uses that information to determine the appropriate signal control strategy.The performance of the model was studied using a simulation of an actual diamond interchange. The simulation study evaluated the model's performance in terms of detection rate, false alarm rate, and mean time to detect. The model's performance was encouraging, and the fuzzy-logic-based approach is considered promising.     

GSM-R中FAS话务量计算

介绍了GSM-R系统的结构,FAS系统及子系统在整个网络中的位置以及系统话务量的计算方法.分别按不同站型计算各站话务量,以此来确定网络的组网方式.     

基于混沌理论的高速公路网短时交通流量预测研究

随着高速公路网的建成及其交通流量的不断增大,对高速路网交通流实时控制和诱导服务的需求日益突出,而高速公路网短时交通流量的预测,不仅是交通流实时控制和诱导服务的基础和依据,而且预测结果的准确性对改善高速公路网的通行能力和服务水平有重要影响。基于混沌时间序列分析和预测的理论,建立了高速公路网短时交通流预测模型,计算给定区域高速公路网多断面短时交通流量预测值,结果表明利用多维混沌时间序列法预测高速公路网短时交通流量可行且具有较高的精度。     

西宁市昆仑路-南关街十字路口交通优化方案

该文针对两宁市昆仑路一南关街十字路口所出现的交通拥堵、车辆延误等问题.利用平面交叉口通行能力理论研究方法对其进行计算分析,从而提出了合理可行的交通优化方案,最后得出解决此交叉口拥堵、车辆延误等问题的结论与建议.     

道路车流量管理控制系统设计

介绍了一种道路车流量管理控制系统的设计方案。它由车流量监测装置、预警信号装置、违规抓拍装置、计算机控制系统、周边道路交通状况显示牌等组成,是一个集监测、预警、控制、指挥于一体的全自动、一体化的系统。     

Reliable sensor deployment for network traffic surveillance

New sensor technologies enable synthesis of disaggregated vehicle information from multiple locations. This paper proposes a reliable facility location model to optimize traffic surveillance benefit from synthesized sensor pairs (e.g., for travel time estimation) in addition to individual sensor flow coverage (e.g., for traffic volume statistics), while considering probabilistic sensor failures. Customized greedy and Lagrangian relaxation algorithms are proposed to solve this problem, and their performance is discussed. Numerical results show that the proposed algorithms solve the problem efficiently. We also discuss managerial insights on how optimal sensor deployment and surveillance benefits vary with surveillance objective and system parameters (such as sensor failure probabilities).     

A shockwave profile model for traffic flow on congested urban arterials

In this paper a new traffic flow model for congested arterial networks, named shockwave profile model (SPM), is presented. Taking advantage of the fact that traffic states within a congested link can be simplified as free-flow, saturated, and jammed conditions, SPM simulates traffic dynamics by analytically deriving the trajectories of four major shockwaves: queuing, discharge, departure, and compression waves. Unlike conventional macroscopic models, in which space is often discretized into small cells for numerical solutions, SPM treats each homogeneous road segment with constant capacity as a section; and the queuing dynamics within each section are described by tracing the shockwave fronts. SPM is particularly suitable for simulating traffic flow on congested signalized arterials especially with queue spillover problems, where the steady-state periodic pattern of queue build-up and dissipation process may break down. Depending on when and where spillover occurs along a signalized arterial, a large number of queuing patterns may be possible. Therefore it becomes difficult to apply the conventional approach directly to track shockwave fronts. To overcome this difficulty, a novel approach is proposed as part of the SPM, in which queue spillover is treated as either extending a red phase or creating new smaller cycles, so that the analytical solutions for tracing the shockwave fronts can be easily applied. Since only the essential features of arterial traffic flow, i.e., queue build-up and dissipation, are considered, SPM significantly reduces the computational load and improves the numerical efficiency. We further validated SPM using real-world traffic signal data collected from a major arterial in the Twin Cities. The results clearly demonstrate the effectiveness and accuracy of the model. We expect that in the future this model can be applied in a number of real-time applications such as arterial performance prediction and signal optimization.     

Increasing the capacity of signalized intersections with separate left turn phases

A separate turn phase is often used on the approach leg to an intersections with heavy left turns. This wastes capacity on the approach because some of its lanes cannot discharge during its green phases. The paper shows that the problem can be eliminated by reorganizing traffic on all the lanes upstream of an intersection using a mid-block pre-signal. If drivers behave deterministically, the capacity that can be achieved is the same as if there were no left turns. However, if the reorganization is too drastic, it may be counterintuitive to drivers. This can be remedied by reorganizing traffic on just some of the available lanes. It is shown that such partial reorganization still increases capacity significantly, even if drivers behave randomly and only one lane is reorganized. The paper shows how to optimize the design of a pre-signal system for a generic intersection. It also identifies both, the potential benefits of the proposed system for a broad class of intersections, and the domain of application where the benefits are most significant.